Bump version to 0.18.0

Bumps [actions/cache](https://github.com/actions/cache) from 3 to 4.
- [Release notes](https://github.com/actions/cache/releases)
- [Changelog](https://github.com/actions/cache/blob/main/RELEASES.md)
- [Commits](https://github.com/actions/cache/compare/v3...v4)

.github/ISSUE_TEMPLATE.md

@@ -1,12 +1,16 @@
 ### Problem Description
 
-Describe the problem you are having, what you expect to happen
-instead, and how to reproduce the problem.
+Describe the problem you are having and what you expect to happen
+instead.
+
+### Steps to Reproduce
+
+Give detailed step-by-step instructions on how to reproduce the problem.
 
 ### Configuration File
 
-Please include the smallest configuration file that reproduces the
-problem you are experiencing:
+Please include the smallest _full_ configuration file that reproduces
+the problem you are experiencing:
 
 ```haskell
 module Main (main) where
@@ -21,4 +25,6 @@ main = xmonad def
 
   - [ ] I've read [CONTRIBUTING.md](https://github.com/xmonad/xmonad/blob/master/CONTRIBUTING.md)
 
-  - [ ] I tested my configuration with [xmonad-testing](https://github.com/xmonad/xmonad-testing)
+  - I tested my configuration
+    - [ ] With `xmonad` version XXX (commit XXX if using git)
+    - [ ] With `xmonad-contrib` version XXX (commit XXX if using git)

.github/PULL_REQUEST_TEMPLATE.md

@@ -9,6 +9,7 @@ behind them.
 
   - [ ] I've confirmed these changes don't belong in xmonad-contrib instead
 
-  - [ ] I tested my changes with [xmonad-testing](https://github.com/xmonad/xmonad-testing)
+  - [ ] I've considered how to best test these changes (property, unit,
+        manually, ...) and concluded: XXX
 
   - [ ] I updated the `CHANGES.md` file

.github/dependabot.yml

@@ -0,0 +1,6 @@
+version: 2
+updates:
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "weekly"

.github/workflows/generatemanpage.yml

@@ -0,0 +1,33 @@
+name: Generate manpage
+
+on:
+  push:
+    branches:
+      - master
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Clone project
+        uses: actions/checkout@v4
+
+      - name: Install dependencies
+        run: |
+          set -ex
+          sudo apt install -y pandoc
+
+      - name: Generate manpage
+        run: |
+          set -ex
+          for d in /opt/ghc/*/bin; do PATH="$d:$PATH"; break; done
+          make -B -C man
+
+      - name: Commit/push if changed
+        run: |
+          set -ex
+          git config user.name 'github-actions[bot]'
+          git config user.email '41898282+github-actions[bot]@users.noreply.github.com'
+          git diff --quiet --exit-code && exit
+          git commit -a -m 'man: Update'
+          git push

.github/workflows/haskell-ci-hackage.patch

@@ -0,0 +1,134 @@
+Piggy-back on the haskell-ci workflow for automatic releases to Hackage.
+
+This extends the workflow with two additional triggers:
+
+ * When the Haskell-CI workflow is triggered manually with a non-empty version
+   input (matching the version in the cabal file), a candidate release is
+   uploaded to Hackage and docs are submitted for it as Hackage can't build
+   them itself (https://github.com/haskell/hackage-server/issues/925).
+
+   Note that promoting the candidate on Hackage discards the uploaded docs
+   (https://github.com/haskell/hackage-server/issues/70). Don't do that.
+
+ * When a release is created on GitHub, a final release is uploaded to Hackage
+   and docs are submitted for it.
+
+The automation uses a special Hackage user: https://hackage.haskell.org/user/xmonad
+and each repo (X11, xmonad, xmonad-contrib) has its own HACKAGE_API_KEY token
+set in GitHub repository secrets.
+
+--- .github/workflows/haskell-ci.yml.orig
++++ .github/workflows/haskell-ci.yml
+@@ -14,8 +14,15 @@
+ #
+ name: Haskell-CI
+ on:
+-  - push
+-  - pull_request
++  push:
++  pull_request:
++  release:
++    types:
++      - published
++  workflow_dispatch:
++    inputs:
++      version:
++        description: candidate version (must match version in cabal file)
+ jobs:
+   linux:
+     name: Haskell-CI - Linux - ${{ matrix.compiler }}
+@@ -33,6 +40,7 @@
+             compilerVersion: 9.8.1
+             setup-method: ghcup
+             allow-failure: false
++            upload: true
+           - compiler: ghc-9.6.4
+             compilerKind: ghc
+             compilerVersion: 9.6.4
+@@ -257,6 +265,10 @@
+       - name: haddock
+         run: |
+           $CABAL v2-haddock --disable-documentation $ARG_COMPILER --with-haddock $HADDOCK $ARG_TESTS $ARG_BENCH all
++      - name: haddock for hackage
++        if: matrix.upload
++        run: |
++          $CABAL v2-haddock $ARG_COMPILER --with-haddock $HADDOCK $ARG_TESTS $ARG_BENCH --haddock-for-hackage --builddir $GITHUB_WORKSPACE/haddock all
+       - name: unconstrained build
+         run: |
+           rm -f cabal.project.local
+@@ -267,3 +279,75 @@
+         with:
+           key: ${{ runner.os }}-${{ matrix.compiler }}-${{ github.sha }}
+           path: ~/.cabal/store
++      - name: upload artifacts (sdist)
++        if: matrix.upload
++        uses: actions/upload-artifact@v3
++        with:
++          path: ${{ github.workspace }}/sdist/*.tar.gz
++      - name: upload artifacts (haddock)
++        if: matrix.upload
++        uses: actions/upload-artifact@v3
++        with:
++          path: ${{ github.workspace }}/haddock/*-docs.tar.gz
++      - name: hackage upload (candidate)
++        if: matrix.upload && github.event_name == 'workflow_dispatch' && github.event.inputs.version != ''
++        shell: bash
++        run: |
++          set -ex
++          PACKAGE_VERSION="${PACKAGE_VERSION#v}"
++          res=$(
++            curl \
++              --silent --show-error --output /dev/stderr --write-out '%{http_code}' \
++              --header "Accept: text/plain" \
++              --header "Authorization: X-ApiKey $HACKAGE_API_KEY" \
++              --form package=@"${GITHUB_WORKSPACE}/sdist/${PACKAGE_NAME}-${PACKAGE_VERSION}.tar.gz" \
++              https://hackage.haskell.org/packages/candidates/
++          )
++          [[ $res == 2?? ]]  # TODO: --fail-with-body once curl 7.76.0 is available
++          res=$(
++            curl \
++              --silent --show-error --output /dev/stderr --write-out '%{http_code}' \
++              -X PUT \
++              --header "Accept: text/plain" \
++              --header "Authorization: X-ApiKey $HACKAGE_API_KEY" \
++              --header "Content-Type: application/x-tar" \
++              --header "Content-Encoding: gzip" \
++              --data-binary @"${GITHUB_WORKSPACE}/haddock/${PACKAGE_NAME}-${PACKAGE_VERSION}-docs.tar.gz" \
++              https://hackage.haskell.org/package/${PACKAGE_NAME}-${PACKAGE_VERSION}/candidate/docs
++          )
++          [[ $res == 2?? ]]
++        env:
++          HACKAGE_API_KEY: ${{ secrets.HACKAGE_API_KEY }}
++          PACKAGE_NAME: ${{ github.event.repository.name }}
++          PACKAGE_VERSION: ${{ github.event.inputs.version }}
++      - name: hackage upload (release)
++        if: matrix.upload && github.event_name == 'release'
++        shell: bash
++        run: |
++          set -ex
++          PACKAGE_VERSION="${PACKAGE_VERSION#v}"
++          res=$(
++            curl \
++              --silent --show-error --output /dev/stderr --write-out '%{http_code}' \
++              --header "Accept: text/plain" \
++              --header "Authorization: X-ApiKey $HACKAGE_API_KEY" \
++              --form package=@"${GITHUB_WORKSPACE}/sdist/${PACKAGE_NAME}-${PACKAGE_VERSION}.tar.gz" \
++              https://hackage.haskell.org/packages/
++          )
++          [[ $res == 2?? ]]  # TODO: --fail-with-body once curl 7.76.0 is available
++          res=$(
++            curl \
++              --silent --show-error --output /dev/stderr --write-out '%{http_code}' \
++              -X PUT \
++              --header "Accept: text/plain" \
++              --header "Authorization: X-ApiKey $HACKAGE_API_KEY" \
++              --header "Content-Type: application/x-tar" \
++              --header "Content-Encoding: gzip" \
++              --data-binary @"${GITHUB_WORKSPACE}/haddock/${PACKAGE_NAME}-${PACKAGE_VERSION}-docs.tar.gz" \
++              https://hackage.haskell.org/package/${PACKAGE_NAME}-${PACKAGE_VERSION}/docs
++          )
++          [[ $res == 2?? ]]
++        env:
++          HACKAGE_API_KEY: ${{ secrets.HACKAGE_API_KEY }}
++          PACKAGE_NAME: ${{ github.event.repository.name }}
++          PACKAGE_VERSION: ${{ github.event.release.tag_name }}

.github/workflows/haskell-ci.yml

@@ -0,0 +1,335 @@
+# This GitHub workflow config has been generated by a script via
+#
+#   haskell-ci 'github' 'cabal.project'
+#
+# To regenerate the script (for example after adjusting tested-with) run
+#
+#   haskell-ci regenerate
+#
+# For more information, see https://github.com/haskell-CI/haskell-ci
+#
+# version: 0.17.20240109
+#
+# REGENDATA ("0.17.20240109",["github","cabal.project"])
+#
+name: Haskell-CI
+on:
+  push:
+  pull_request:
+  release:
+    types:
+      - published
+  workflow_dispatch:
+    inputs:
+      version:
+        description: candidate version (must match version in cabal file)
+jobs:
+  linux:
+    name: Haskell-CI - Linux - ${{ matrix.compiler }}
+    runs-on: ubuntu-20.04
+    timeout-minutes:
+      60
+    container:
+      image: buildpack-deps:bionic
+    continue-on-error: ${{ matrix.allow-failure }}
+    strategy:
+      matrix:
+        include:
+          - compiler: ghc-9.8.1
+            compilerKind: ghc
+            compilerVersion: 9.8.1
+            setup-method: ghcup
+            allow-failure: false
+            upload: true
+          - compiler: ghc-9.6.4
+            compilerKind: ghc
+            compilerVersion: 9.6.4
+            setup-method: ghcup
+            allow-failure: false
+          - compiler: ghc-9.4.8
+            compilerKind: ghc
+            compilerVersion: 9.4.8
+            setup-method: ghcup
+            allow-failure: false
+          - compiler: ghc-9.2.8
+            compilerKind: ghc
+            compilerVersion: 9.2.8
+            setup-method: ghcup
+            allow-failure: false
+          - compiler: ghc-9.0.2
+            compilerKind: ghc
+            compilerVersion: 9.0.2
+            setup-method: ghcup
+            allow-failure: false
+          - compiler: ghc-8.10.7
+            compilerKind: ghc
+            compilerVersion: 8.10.7
+            setup-method: ghcup
+            allow-failure: false
+          - compiler: ghc-8.8.4
+            compilerKind: ghc
+            compilerVersion: 8.8.4
+            setup-method: hvr-ppa
+            allow-failure: false
+          - compiler: ghc-8.6.5
+            compilerKind: ghc
+            compilerVersion: 8.6.5
+            setup-method: hvr-ppa
+            allow-failure: false
+      fail-fast: false
+    steps:
+      - name: apt
+        run: |
+          apt-get update
+          apt-get install -y --no-install-recommends gnupg ca-certificates dirmngr curl git software-properties-common libtinfo5
+          if [ "${{ matrix.setup-method }}" = ghcup ]; then
+            mkdir -p "$HOME/.ghcup/bin"
+            curl -sL https://downloads.haskell.org/ghcup/0.1.20.0/x86_64-linux-ghcup-0.1.20.0 > "$HOME/.ghcup/bin/ghcup"
+            chmod a+x "$HOME/.ghcup/bin/ghcup"
+            "$HOME/.ghcup/bin/ghcup" install ghc "$HCVER" || (cat "$HOME"/.ghcup/logs/*.* && false)
+            "$HOME/.ghcup/bin/ghcup" install cabal 3.10.2.0 || (cat "$HOME"/.ghcup/logs/*.* && false)
+            apt-get update
+            apt-get install -y libx11-dev libxext-dev libxinerama-dev libxrandr-dev libxss-dev
+          else
+            apt-add-repository -y 'ppa:hvr/ghc'
+            apt-get update
+            apt-get install -y "$HCNAME" libx11-dev libxext-dev libxinerama-dev libxrandr-dev libxss-dev
+            mkdir -p "$HOME/.ghcup/bin"
+            curl -sL https://downloads.haskell.org/ghcup/0.1.20.0/x86_64-linux-ghcup-0.1.20.0 > "$HOME/.ghcup/bin/ghcup"
+            chmod a+x "$HOME/.ghcup/bin/ghcup"
+            "$HOME/.ghcup/bin/ghcup" install cabal 3.10.2.0 || (cat "$HOME"/.ghcup/logs/*.* && false)
+          fi
+        env:
+          HCKIND: ${{ matrix.compilerKind }}
+          HCNAME: ${{ matrix.compiler }}
+          HCVER: ${{ matrix.compilerVersion }}
+      - name: Set PATH and environment variables
+        run: |
+          echo "$HOME/.cabal/bin" >> $GITHUB_PATH
+          echo "LANG=C.UTF-8" >> "$GITHUB_ENV"
+          echo "CABAL_DIR=$HOME/.cabal" >> "$GITHUB_ENV"
+          echo "CABAL_CONFIG=$HOME/.cabal/config" >> "$GITHUB_ENV"
+          HCDIR=/opt/$HCKIND/$HCVER
+          if [ "${{ matrix.setup-method }}" = ghcup ]; then
+            HC=$("$HOME/.ghcup/bin/ghcup" whereis ghc "$HCVER")
+            HCPKG=$(echo "$HC" | sed 's#ghc$#ghc-pkg#')
+            HADDOCK=$(echo "$HC" | sed 's#ghc$#haddock#')
+            echo "HC=$HC" >> "$GITHUB_ENV"
+            echo "HCPKG=$HCPKG" >> "$GITHUB_ENV"
+            echo "HADDOCK=$HADDOCK" >> "$GITHUB_ENV"
+            echo "CABAL=$HOME/.ghcup/bin/cabal-3.10.2.0 -vnormal+nowrap" >> "$GITHUB_ENV"
+          else
+            HC=$HCDIR/bin/$HCKIND
+            echo "HC=$HC" >> "$GITHUB_ENV"
+            echo "HCPKG=$HCDIR/bin/$HCKIND-pkg" >> "$GITHUB_ENV"
+            echo "HADDOCK=$HCDIR/bin/haddock" >> "$GITHUB_ENV"
+            echo "CABAL=$HOME/.ghcup/bin/cabal-3.10.2.0 -vnormal+nowrap" >> "$GITHUB_ENV"
+          fi
+
+          HCNUMVER=$(${HC} --numeric-version|perl -ne '/^(\d+)\.(\d+)\.(\d+)(\.(\d+))?$/; print(10000 * $1 + 100 * $2 + ($3 == 0 ? $5 != 1 : $3))')
+          echo "HCNUMVER=$HCNUMVER" >> "$GITHUB_ENV"
+          echo "ARG_TESTS=--enable-tests" >> "$GITHUB_ENV"
+          echo "ARG_BENCH=--enable-benchmarks" >> "$GITHUB_ENV"
+          echo "HEADHACKAGE=false" >> "$GITHUB_ENV"
+          echo "ARG_COMPILER=--$HCKIND --with-compiler=$HC" >> "$GITHUB_ENV"
+          echo "GHCJSARITH=0" >> "$GITHUB_ENV"
+        env:
+          HCKIND: ${{ matrix.compilerKind }}
+          HCNAME: ${{ matrix.compiler }}
+          HCVER: ${{ matrix.compilerVersion }}
+      - name: env
+        run: |
+          env
+      - name: write cabal config
+        run: |
+          mkdir -p $CABAL_DIR
+          cat >> $CABAL_CONFIG <<EOF
+          remote-build-reporting: anonymous
+          write-ghc-environment-files: never
+          remote-repo-cache: $CABAL_DIR/packages
+          logs-dir:          $CABAL_DIR/logs
+          world-file:        $CABAL_DIR/world
+          extra-prog-path:   $CABAL_DIR/bin
+          symlink-bindir:    $CABAL_DIR/bin
+          installdir:        $CABAL_DIR/bin
+          build-summary:     $CABAL_DIR/logs/build.log
+          store-dir:         $CABAL_DIR/store
+          install-dirs user
+            prefix: $CABAL_DIR
+          repository hackage.haskell.org
+            url: http://hackage.haskell.org/
+          EOF
+          cat >> $CABAL_CONFIG <<EOF
+          program-default-options
+            ghc-options: $GHCJOBS +RTS -M3G -RTS
+          EOF
+          cat $CABAL_CONFIG
+      - name: versions
+        run: |
+          $HC --version || true
+          $HC --print-project-git-commit-id || true
+          $CABAL --version || true
+      - name: update cabal index
+        run: |
+          $CABAL v2-update -v
+      - name: install cabal-plan
+        run: |
+          mkdir -p $HOME/.cabal/bin
+          curl -sL https://github.com/haskell-hvr/cabal-plan/releases/download/v0.7.3.0/cabal-plan-0.7.3.0-x86_64-linux.xz > cabal-plan.xz
+          echo 'f62ccb2971567a5f638f2005ad3173dba14693a45154c1508645c52289714cb2  cabal-plan.xz' | sha256sum -c -
+          xz -d < cabal-plan.xz > $HOME/.cabal/bin/cabal-plan
+          rm -f cabal-plan.xz
+          chmod a+x $HOME/.cabal/bin/cabal-plan
+          cabal-plan --version
+      - name: checkout
+        uses: actions/checkout@v3
+        with:
+          path: source
+      - name: initial cabal.project for sdist
+        run: |
+          touch cabal.project
+          echo "packages: $GITHUB_WORKSPACE/source/." >> cabal.project
+          cat cabal.project
+      - name: sdist
+        run: |
+          mkdir -p sdist
+          $CABAL sdist all --output-dir $GITHUB_WORKSPACE/sdist
+      - name: unpack
+        run: |
+          mkdir -p unpacked
+          find sdist -maxdepth 1 -type f -name '*.tar.gz' -exec tar -C $GITHUB_WORKSPACE/unpacked -xzvf {} \;
+      - name: generate cabal.project
+        run: |
+          PKGDIR_xmonad="$(find "$GITHUB_WORKSPACE/unpacked" -maxdepth 1 -type d -regex '.*/xmonad-[0-9.]*')"
+          echo "PKGDIR_xmonad=${PKGDIR_xmonad}" >> "$GITHUB_ENV"
+          rm -f cabal.project cabal.project.local
+          touch cabal.project
+          touch cabal.project.local
+          echo "packages: ${PKGDIR_xmonad}" >> cabal.project
+          echo "package xmonad" >> cabal.project
+          echo "    ghc-options: -Werror=missing-methods" >> cabal.project
+          cat >> cabal.project <<EOF
+          optimization: False
+
+          package xmonad
+            flags: +pedantic
+          EOF
+          $HCPKG list --simple-output --names-only | perl -ne 'for (split /\s+/) { print "constraints: $_ installed\n" unless /^(xmonad)$/; }' >> cabal.project.local
+          cat cabal.project
+          cat cabal.project.local
+      - name: dump install plan
+        run: |
+          $CABAL v2-build $ARG_COMPILER $ARG_TESTS $ARG_BENCH --dry-run all
+          cabal-plan
+      - name: restore cache
+        uses: actions/cache/restore@v3
+        with:
+          key: ${{ runner.os }}-${{ matrix.compiler }}-${{ github.sha }}
+          path: ~/.cabal/store
+          restore-keys: ${{ runner.os }}-${{ matrix.compiler }}-
+      - name: install dependencies
+        run: |
+          $CABAL v2-build $ARG_COMPILER --disable-tests --disable-benchmarks --dependencies-only -j2 all
+          $CABAL v2-build $ARG_COMPILER $ARG_TESTS $ARG_BENCH --dependencies-only -j2 all
+      - name: build w/o tests
+        run: |
+          $CABAL v2-build $ARG_COMPILER --disable-tests --disable-benchmarks all
+      - name: build
+        run: |
+          $CABAL v2-build $ARG_COMPILER $ARG_TESTS $ARG_BENCH all --write-ghc-environment-files=always
+      - name: tests
+        run: |
+          $CABAL v2-test $ARG_COMPILER $ARG_TESTS $ARG_BENCH all --test-show-details=direct
+      - name: cabal check
+        run: |
+          cd ${PKGDIR_xmonad} || false
+          ${CABAL} -vnormal check
+      - name: haddock
+        run: |
+          $CABAL v2-haddock --disable-documentation $ARG_COMPILER --with-haddock $HADDOCK $ARG_TESTS $ARG_BENCH all
+      - name: haddock for hackage
+        if: matrix.upload
+        run: |
+          $CABAL v2-haddock $ARG_COMPILER --with-haddock $HADDOCK $ARG_TESTS $ARG_BENCH --haddock-for-hackage --builddir $GITHUB_WORKSPACE/haddock all
+      - name: unconstrained build
+        run: |
+          rm -f cabal.project.local
+          $CABAL v2-build $ARG_COMPILER --disable-tests --disable-benchmarks all
+      - name: save cache
+        uses: actions/cache/save@v3
+        if: always()
+        with:
+          key: ${{ runner.os }}-${{ matrix.compiler }}-${{ github.sha }}
+          path: ~/.cabal/store
+      - name: upload artifacts (sdist)
+        if: matrix.upload
+        uses: actions/upload-artifact@v3
+        with:
+          path: ${{ github.workspace }}/sdist/*.tar.gz
+      - name: upload artifacts (haddock)
+        if: matrix.upload
+        uses: actions/upload-artifact@v3
+        with:
+          path: ${{ github.workspace }}/haddock/*-docs.tar.gz
+      - name: hackage upload (candidate)
+        if: matrix.upload && github.event_name == 'workflow_dispatch' && github.event.inputs.version != ''
+        shell: bash
+        run: |
+          set -ex
+          PACKAGE_VERSION="${PACKAGE_VERSION#v}"
+          res=$(
+            curl \
+              --silent --show-error --output /dev/stderr --write-out '%{http_code}' \
+              --header "Accept: text/plain" \
+              --header "Authorization: X-ApiKey $HACKAGE_API_KEY" \
+              --form package=@"${GITHUB_WORKSPACE}/sdist/${PACKAGE_NAME}-${PACKAGE_VERSION}.tar.gz" \
+              https://hackage.haskell.org/packages/candidates/
+          )
+          [[ $res == 2?? ]]  # TODO: --fail-with-body once curl 7.76.0 is available
+          res=$(
+            curl \
+              --silent --show-error --output /dev/stderr --write-out '%{http_code}' \
+              -X PUT \
+              --header "Accept: text/plain" \
+              --header "Authorization: X-ApiKey $HACKAGE_API_KEY" \
+              --header "Content-Type: application/x-tar" \
+              --header "Content-Encoding: gzip" \
+              --data-binary @"${GITHUB_WORKSPACE}/haddock/${PACKAGE_NAME}-${PACKAGE_VERSION}-docs.tar.gz" \
+              https://hackage.haskell.org/package/${PACKAGE_NAME}-${PACKAGE_VERSION}/candidate/docs
+          )
+          [[ $res == 2?? ]]
+        env:
+          HACKAGE_API_KEY: ${{ secrets.HACKAGE_API_KEY }}
+          PACKAGE_NAME: ${{ github.event.repository.name }}
+          PACKAGE_VERSION: ${{ github.event.inputs.version }}
+      - name: hackage upload (release)
+        if: matrix.upload && github.event_name == 'release'
+        shell: bash
+        run: |
+          set -ex
+          PACKAGE_VERSION="${PACKAGE_VERSION#v}"
+          res=$(
+            curl \
+              --silent --show-error --output /dev/stderr --write-out '%{http_code}' \
+              --header "Accept: text/plain" \
+              --header "Authorization: X-ApiKey $HACKAGE_API_KEY" \
+              --form package=@"${GITHUB_WORKSPACE}/sdist/${PACKAGE_NAME}-${PACKAGE_VERSION}.tar.gz" \
+              https://hackage.haskell.org/packages/
+          )
+          [[ $res == 2?? ]]  # TODO: --fail-with-body once curl 7.76.0 is available
+          res=$(
+            curl \
+              --silent --show-error --output /dev/stderr --write-out '%{http_code}' \
+              -X PUT \
+              --header "Accept: text/plain" \
+              --header "Authorization: X-ApiKey $HACKAGE_API_KEY" \
+              --header "Content-Type: application/x-tar" \
+              --header "Content-Encoding: gzip" \
+              --data-binary @"${GITHUB_WORKSPACE}/haddock/${PACKAGE_NAME}-${PACKAGE_VERSION}-docs.tar.gz" \
+              https://hackage.haskell.org/package/${PACKAGE_NAME}-${PACKAGE_VERSION}/docs
+          )
+          [[ $res == 2?? ]]
+        env:
+          HACKAGE_API_KEY: ${{ secrets.HACKAGE_API_KEY }}
+          PACKAGE_NAME: ${{ github.event.repository.name }}
+          PACKAGE_VERSION: ${{ github.event.release.tag_name }}

.github/workflows/hlint.yaml

@@ -0,0 +1,22 @@
+name: hlint
+
+on:
+  push:
+  pull_request:
+
+jobs:
+  hlint:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v4
+
+    - name: 'Set up HLint'
+      uses: haskell-actions/hlint-setup@v2
+      with:
+        version: '3.5'
+
+    - name: 'Run HLint'
+      uses: haskell-actions/hlint-run@v2
+      with:
+        path: '.'
+        fail-on: status

.github/workflows/nix.yml

@@ -0,0 +1,25 @@
+name: Nix
+
+on:
+  push:
+  pull_request:
+
+jobs:
+  build:
+    runs-on: ubuntu-20.04  # FIXME
+    name: Nix Flake - Linux
+    permissions:
+      contents: read
+    steps:
+      - name: Install Nix
+        uses: cachix/install-nix-action@v25
+        with:
+          install_url: https://nixos-nix-install-tests.cachix.org/serve/i6laym9jw3wg9mw6ncyrk6gjx4l34vvx/install
+          install_options: '--tarball-url-prefix https://nixos-nix-install-tests.cachix.org/serve'
+          extra_nix_config: |
+            experimental-features = nix-command flakes
+            access-tokens = github.com=${{ secrets.GITHUB_TOKEN }}
+      - name: Clone project
+        uses: actions/checkout@v4
+      - name: Build
+        run: nix build --print-build-logs

.github/workflows/packdeps.yml

@@ -0,0 +1,49 @@
+name: Packdeps
+
+on:
+  workflow_dispatch:
+  schedule:
+    # Run every Saturday
+    - cron: '0 3 * * 6'
+
+jobs:
+  packdeps:
+    name: Packdeps
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Clone project
+        uses: actions/checkout@v4
+      - name: Setup Haskell
+        uses: haskell-actions/setup@v2
+        with:
+          # packdeps doesn't build with newer as of 2021-10
+          ghc-version: '8.8'
+      - name: Install packdeps
+        run: |
+          set -ex
+          cd  # go somewhere without a cabal.project
+          cabal install packdeps
+      - name: Check package bounds (all)
+        continue-on-error: true
+        run: |
+          set -ex
+          packdeps \
+            --exclude X11 \
+            *.cabal
+      - name: Check package bounds (preferred)
+        run: |
+          set -ex
+          packdeps \
+            --preferred \
+            --exclude X11 \
+            *.cabal
+
+  workflow-keepalive:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Re-enable workflow
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          gh api -X PUT repos/${{ github.repository }}/actions/workflows/packdeps.yml/enable

.github/workflows/stack.yml

@@ -0,0 +1,77 @@
+name: Stack
+
+on:
+  push:
+  pull_request:
+
+jobs:
+  build:
+    name: Stack CI - Linux - ${{ matrix.resolver }}
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - resolver: lts-14  # GHC 8.6
+          - resolver: lts-16  # GHC 8.8
+          - resolver: lts-18  # GHC 8.10
+          - resolver: lts-19  # GHC 9.0
+          - resolver: lts-20  # GHC 9.2
+          - resolver: lts-21  # GHC 9.4
+
+    steps:
+      - name: Clone project
+        uses: actions/checkout@v4
+
+      - name: Install C dependencies
+        run: |
+          set -ex
+          sudo apt update -y
+          sudo apt install -y \
+            libx11-dev \
+            libxext-dev \
+            libxinerama-dev \
+            libxrandr-dev \
+            libxss-dev \
+            #
+
+      - name: Refresh caches once a month
+        id: cache-date
+        # GHA writes caches on the first miss and then never updates them again;
+        # force updating the cache at least once a month. Additionally, the
+        # date is prefixed with an epoch number to let us manually refresh the
+        # cache when needed. This is a workaround for https://github.com/actions/cache/issues/2
+        run: |
+          date +date=1-%Y-%m >> $GITHUB_OUTPUT
+
+      - name: Cache Haskell package metadata
+        uses: actions/cache@v4
+        with:
+          path: ~/.stack/pantry
+          key: stack-pantry-${{ runner.os }}-${{ steps.cache-date.outputs.date }}
+
+      - name: Cache Haskell dependencies
+        uses: actions/cache@v4
+        with:
+          path: |
+            ~/.stack/*
+            !~/.stack/pantry
+            !~/.stack/programs
+          key: stack-${{ runner.os }}-${{ matrix.resolver }}-${{ steps.cache-date.outputs.date }}-${{ hashFiles('stack.yaml') }}-${{ hashFiles('*.cabal') }}
+          restore-keys: |
+            stack-${{ runner.os }}-${{ matrix.resolver }}-${{ steps.cache-date.outputs.date }}-${{ hashFiles('stack.yaml') }}-
+            stack-${{ runner.os }}-${{ matrix.resolver }}-${{ steps.cache-date.outputs.date }}-
+
+      - name: Update hackage index
+        # always update index to prevent the shared ~/.stack/pantry cache from being empty
+        run: |
+          set -ex
+          stack update
+
+      - name: Build and test
+        run: |
+          set -ex
+          stack test \
+            --fast --no-terminal \
+            --resolver=${{ matrix.resolver }} --system-ghc \
+            --flag=xmonad:pedantic

.gitignore

@@ -27,3 +27,6 @@ tags
 /cabal.sandbox.config
 /dist-newstyle/
 /dist/
+
+# nix artifacts
+result

.hlint.yaml

@@ -0,0 +1,2 @@
+# Ignore these warnings.
+- ignore: {name: "Use camelCase"}

.mailmap

@@ -0,0 +1,38 @@
+Adam Plaice <plaice.adam+github@gmail.com>
+Brandon S Allbery KF8NH <allbery.b@gmail.com>
+Brent Yorgey <byorgey@gmail.com> <byorgey@cis.upenn.edu>
+Conrad Irwin <conrad.irwin@gmail.com>
+Daniel Neri <daniel.neri@sigicom.com> <daniel.neri@sigicom.se>
+Daniel Schoepe <daniel.schoepe@gmail.com> <asgaroth_@gmx.de>
+Daniel Wagner <me@dmwit.com> <daniel@wagner-home.com>
+David Glasser <glasser@mit.edu>
+Deven Lahoti <deven.lahoti@gmail.com>
+Devin Mullins <devin.mullins@gmail.com> <me@twifkak.com>
+Don Stewart <dons00@gmail.com> <dons@cse.unsw.edu.au>
+Don Stewart <dons00@gmail.com> <dons@galois.com>
+Felix Springer <felixspringer149@gmail.com> <39434424+jumper149@users.noreply.github.com>
+Gwern Branwen <gwern@gwern.net> <gwern0@gmail.com>
+Lukas Mai <l.mai@web.de>
+Marshall Lochbaum <mwlochbaum@gmail.com>
+Michael G. Sloan <mgsloan@gmail.com>
+Neil Mitchell <ndmitchell@gmail.com> <http://www.cs.york.ac.uk/~ndm/>
+Neil Mitchell <ndmitchell@gmail.com> Neil Mitchell <unknown>
+Nick Burlett <nickburlett@mac.com>
+Nicolas Pouillard <nicolas.pouillard@gmail.com>
+Nik Nyby <nnyby@columbia.edu>
+Peter J. Jones <pjones@devalot.com>
+Peter J. Jones <pjones@devalot.com> <pjones@pmade.com>
+Robert Marlow <bobstopper@bobturf.org>
+Robert Marlow <bobstopper@bobturf.org> <robreim@bobturf.org>
+Sam Hughes <hughes@rpi.edu>
+Shae Erisson <shae@ScannedInAvian.com>
+Sibi Prabakaran <sibi@psibi.in>
+Sibi Prabakaran <sibi@psibi.in> <psibi2000@gmail.com>
+Spencer Janssen <spencerjanssen@gmail.com> <sjanssen@cse.unl.edu>
+Timothy Hobbs <tim.thelion@gmail.com>
+Tomas Janousek <tomi@nomi.cz>
+Valery V. Vorotyntsev <valery.vv@gmail.com>
+Vanessa McHale <vamchale@gmail.com> <vanessa.mchale@reconfigure.io>
+Wirt Wolff <wirtwolff@gmail.com>
+
+slotThe <soliditsallgood@mailbox.org> <50166980+slotThe@users.noreply.github.com>

.travis.yml

@@ -1,135 +0,0 @@
-# This Travis job script has been generated by a script via
-#
-#   runghc make_travis_yml_2.hs '-o' '.travis.yml' 'xmonad.cabal' 'libxrandr-dev'
-#
-# For more information, see https://github.com/haskell-CI/haskell-ci
-#
-language: c
-sudo: false
-
-git:
-  submodules: false  # whether to recursively clone submodules
-
-cache:
-  directories:
-    - $HOME/.cabal/packages
-    - $HOME/.cabal/store
-
-before_cache:
-  - rm -fv $HOME/.cabal/packages/hackage.haskell.org/build-reports.log
-  # remove files that are regenerated by 'cabal update'
-  - rm -fv $HOME/.cabal/packages/hackage.haskell.org/00-index.*
-  - rm -fv $HOME/.cabal/packages/hackage.haskell.org/*.json
-  - rm -fv $HOME/.cabal/packages/hackage.haskell.org/01-index.cache
-  - rm -fv $HOME/.cabal/packages/hackage.haskell.org/01-index.tar
-  - rm -fv $HOME/.cabal/packages/hackage.haskell.org/01-index.tar.idx
-
-  - rm -rfv $HOME/.cabal/packages/head.hackage
-
-matrix:
-  include:
-    - compiler: "ghc-8.6.1"
-      env: GHCHEAD=true
-      addons: {apt: {packages: [ghc-ppa-tools,cabal-install-head,ghc-8.6.1,libxrandr-dev], sources: [hvr-ghc]}}
-    - compiler: "ghc-8.4.3"
-    # env: TEST=--disable-tests BENCH=--disable-benchmarks
-      addons: {apt: {packages: [ghc-ppa-tools,cabal-install-2.2,ghc-8.4.3,libxrandr-dev], sources: [hvr-ghc]}}
-    - compiler: "ghc-8.2.2"
-    # env: TEST=--disable-tests BENCH=--disable-benchmarks
-      addons: {apt: {packages: [ghc-ppa-tools,cabal-install-2.2,ghc-8.2.2,libxrandr-dev], sources: [hvr-ghc]}}
-    - compiler: "ghc-8.0.2"
-    # env: TEST=--disable-tests BENCH=--disable-benchmarks
-      addons: {apt: {packages: [ghc-ppa-tools,cabal-install-2.2,ghc-8.0.2,libxrandr-dev], sources: [hvr-ghc]}}
-
-  allow_failures:
-    - compiler: "ghc-8.6.1"
-
-before_install:
-  - HC=${CC}
-  - HCPKG=${HC/ghc/ghc-pkg}
-  - unset CC
-  - ROOTDIR=$(pwd)
-  - mkdir -p $HOME/.local/bin
-  - "PATH=/opt/ghc/bin:/opt/ghc-ppa-tools/bin:$HOME/local/bin:$PATH"
-  - HCNUMVER=$(( $(${HC} --numeric-version|sed -E 's/([0-9]+)\.([0-9]+)\.([0-9]+).*/\1 * 10000 + \2 * 100 + \3/') ))
-  - echo $HCNUMVER
-
-install:
-  - cabal --version
-  - echo "$(${HC} --version) [$(${HC} --print-project-git-commit-id 2> /dev/null || echo '?')]"
-  - BENCH=${BENCH---enable-benchmarks}
-  - TEST=${TEST---enable-tests}
-  - HADDOCK=${HADDOCK-true}
-  - UNCONSTRAINED=${UNCONSTRAINED-true}
-  - NOINSTALLEDCONSTRAINTS=${NOINSTALLEDCONSTRAINTS-false}
-  - GHCHEAD=${GHCHEAD-false}
-  - travis_retry cabal update -v
-  - "sed -i.bak 's/^jobs:/-- jobs:/' ${HOME}/.cabal/config"
-  - rm -fv cabal.project cabal.project.local
-  # Overlay Hackage Package Index for GHC HEAD: https://github.com/hvr/head.hackage
-  - |
-    if $GHCHEAD; then
-      sed -i 's/-- allow-newer: .*/allow-newer: *:base/' ${HOME}/.cabal/config
-      for pkg in $($HCPKG list --simple-output); do pkg=$(echo $pkg | sed 's/-[^-]*$//'); sed -i "s/allow-newer: /allow-newer: *:$pkg, /" ${HOME}/.cabal/config; done
-
-      echo 'repository head.hackage'                                                        >> ${HOME}/.cabal/config
-      echo '   url: http://head.hackage.haskell.org/'                                       >> ${HOME}/.cabal/config
-      echo '   secure: True'                                                                >> ${HOME}/.cabal/config
-      echo '   root-keys: 07c59cb65787dedfaef5bd5f987ceb5f7e5ebf88b904bbd4c5cbdeb2ff71b740' >> ${HOME}/.cabal/config
-      echo '              2e8555dde16ebd8df076f1a8ef13b8f14c66bad8eafefd7d9e37d0ed711821fb' >> ${HOME}/.cabal/config
-      echo '              8f79fd2389ab2967354407ec852cbe73f2e8635793ac446d09461ffb99527f6e' >> ${HOME}/.cabal/config
-      echo '   key-threshold: 3'                                                            >> ${HOME}/.cabal.config
-
-      grep -Ev -- '^\s*--' ${HOME}/.cabal/config | grep -Ev '^\s*$'
-
-      cabal new-update head.hackage -v
-    fi
-  - grep -Ev -- '^\s*--' ${HOME}/.cabal/config | grep -Ev '^\s*$'
-  - "printf 'packages: \".\"\\n' > cabal.project"
-  - "if [ $HCNUMVER -lt 80600 ]; then printf 'package xmonad\\n  flags: +generatemanpage\n' >> cabal.project; fi"
-  - touch cabal.project.local
-  - "if ! $NOINSTALLEDCONSTRAINTS; then for pkg in $($HCPKG list --simple-output); do echo $pkg  | grep -vw -- xmonad | sed 's/^/constraints: /' | sed 's/-[^-]*$/ installed/' >> cabal.project.local; done; fi"
-  - cat cabal.project || true
-  - cat cabal.project.local || true
-  - if [ -f "./configure.ac" ]; then
-      (cd "." && autoreconf -i);
-    fi
-  - rm -f cabal.project.freeze
-  - cabal new-build -w ${HC} ${TEST} ${BENCH} --project-file="cabal.project" --dep -j2 all
-  - cabal new-build -w ${HC} --disable-tests --disable-benchmarks --project-file="cabal.project" --dep -j2 all
-  - rm -rf .ghc.environment.* "."/dist
-  - DISTDIR=$(mktemp -d /tmp/dist-test.XXXX)
-
-# Here starts the actual work to be performed for the package under test;
-# any command which exits with a non-zero exit code causes the build to fail.
-script:
-  # test that source-distributions can be generated
-  - (cd "." && cabal sdist)
-  - mv "."/dist/xmonad-*.tar.gz ${DISTDIR}/
-  - cd ${DISTDIR} || false
-  - find . -maxdepth 1 -name '*.tar.gz' -exec tar -xvf '{}' \;
-  - "printf 'packages: xmonad-*/*.cabal\\n' > cabal.project"
-  - "if [ $HCNUMVER -lt 80600 ]; then printf 'package xmonad\\n  flags: +generatemanpage\n' >> cabal.project; fi"
-  - touch cabal.project.local
-  - "if ! $NOINSTALLEDCONSTRAINTS; then for pkg in $($HCPKG list --simple-output); do echo $pkg  | grep -vw -- xmonad | sed 's/^/constraints: /' | sed 's/-[^-]*$/ installed/' >> cabal.project.local; done; fi"
-  - cat cabal.project || true
-  - cat cabal.project.local || true
-  # this builds all libraries and executables (without tests/benchmarks)
-  - cabal new-build -w ${HC} --disable-tests --disable-benchmarks all
-
-  # build & run tests, build benchmarks
-  - cabal new-build -w ${HC} ${TEST} ${BENCH} all
-  - if [ "x$TEST" = "x--enable-tests" ]; then cabal new-test -w ${HC} ${TEST} ${BENCH} all; fi
-
-  # cabal check
-  - (cd xmonad-* && cabal check)
-
-  # haddock
-  - rm -rf ./dist-newstyle
-  - if $HADDOCK; then cabal new-haddock -w ${HC} ${TEST} ${BENCH} all; else echo "Skipping haddock generation";fi
-
-  # Build without installed constraints for packages in global-db
-  - if $UNCONSTRAINED; then rm -f cabal.project.local; echo cabal new-build -w ${HC} --disable-tests --disable-benchmarks all; else echo "Not building without installed constraints"; fi
-
-# REGENDATA ["-o",".travis.yml","xmonad.cabal","libxrandr-dev"]
-# EOF

CHANGES.md

@@ -1,6 +1,155 @@
 # Change Log / Release Notes
 
-## unknown (unknown)
+## 0.18.0 (February 3, 2024)
+
+### Breaking Changes
+
+* Dropped support for GHC 8.4.
+
+### Enhancements
+
+* Exported `sendRestart` and `sendReplace` from `XMonad.Operations`.
+
+* Exported `buildLaunch` from `XMonad.Main`.
+
+* `Tall` does not draw windows with zero area.
+
+* `XMonad.Operations.floatLocation` now applies size hints. This means windows
+  will snap to these hints as soon as they're floated (mouse move, keybinding).
+  Previously that only happened on mouse resize.
+
+* Recompilation now detects `flake.nix` and `default.nix` (can be a
+  symlink) and switches to using `nix build` as appropriate.
+
+* Added `unGrab` to `XMonad.Operations`; this releases XMonad's passive
+  keyboard grab, so other applications (like `scrot`) can do their
+  thing.
+
+### Bug Fixes
+
+* Duplicated floats (e.g. from X.A.CopyToAll) no longer escape to inactive
+  screens.
+
+## 0.17.2 (April 2, 2023)
+
+### Bug Fixes
+
+  * Fixed the build with GHC 9.6.
+
+## 0.17.1 (September 3, 2022)
+
+### Enhancements
+
+  * Added custom cursor shapes for resizing and moving windows.
+
+  * Exported `cacheNumlockMask` and `mkGrabs` from `XMonad.Operations`.
+
+  * Added `willFloat` function to `XMonad.ManageHooks` to detect whether the
+    (about to be) managed window will be a floating window or not.
+
+### Bug Fixes
+
+  * Fixed border color of windows with alpha channel. Now all windows have the
+    same opaque border color.
+
+  * Change the main loop to try to avoid [GHC bug 21708] on systems
+    running GHC 9.2 up to version 9.2.3. The issue has been fixed in
+    [GHC 9.2.4] and all later releases.
+
+[GHC bug 21708]: https://gitlab.haskell.org/ghc/ghc/-/issues/21708
+[GHC 9.2.4]: https://discourse.haskell.org/t/ghc-9-2-4-released/4851
+
+## 0.17.0 (October 27, 2021)
+
+### Enhancements
+
+  * Migrated `X.L.LayoutCombinators.(|||)` into `XMonad.Layout`, providing the
+    ability to directly jump to a layout with the `JumpToLayout` message.
+
+  * Recompilation now detects `stack.yaml` (can be a symlink) alongside
+    `xmonad.hs` and switches to using `stack ghc`. We also updated INSTALL.md
+    with instructions for cabal-install that lead to correct recompilation.
+
+    Deprecation warnings during recompilation are no longer suppressed to make
+    it easier for us to clean up the codebase. These can still be suppressed
+    manually using an `OPTIONS_GHC` pragma with `-Wno-deprecations`.
+
+  * Improve handling of XDG directories.
+
+      1. If all three of xmonad's environment variables (`XMONAD_DATA_DIR,`
+         `XMONAD_CONFIG_DIR`, and `XMONAD_CACHE_DIR`) are set, use them.
+      2. If there is a build script called `build` (see [these build scripts]
+         for usage examples) or configuration `xmonad.hs` in `~/.xmonad`, set
+         all three directories to `~/.xmonad`.
+      3. Otherwise, use the `xmonad` directory in `XDG_DATA_HOME`,
+         `XDG_CONFIG_HOME`, and `XDG_CACHE_HOME` (or their respective
+         fallbacks). These directories are created if necessary.
+
+    In the cases of 1. and 3., the build script or executable is expected to be
+    in the config dir.
+
+    Additionally, the xmonad config binary and intermediate object files were
+    moved to the cache directory (only relevant if using XDG or
+    `XMONAD_CACHE_DIR`).
+
+  * Added `Foldable`, `Functor`, and `Traversable` instances for `Stack`.
+
+  * Added `Typeable layout` constraint to `LayoutClass`, making it possible to
+    cast `Layout` back into a concrete type and extract current layout state
+    from it.
+
+  * Export constructor for `Choose` and `CLR` from `Module.Layout` to allow
+    pattern-matching on the left and right sub-layouts of `Choose l r a`.
+
+  * Added `withUnfocused` function to `XMonad.Operations`, allowing for `X`
+    operations to be applied to unfocused windows.
+
+[these build scripts]: https://github.com/xmonad/xmonad-testing/tree/master/build-scripts
+
+### Bug Fixes
+
+  * Fixed a bug when using multiple screens with different dimensions, causing
+    some floating windows to be smaller/larger than the size they requested.
+
+  * Compatibility with GHC 9.0
+
+  * Fixed dunst notifications being obscured when moving floats.
+    https://github.com/xmonad/xmonad/issues/208
+
+### Breaking Changes
+
+  * Made `(<&&>)` and `(<||>)` non-strict in their right operand; i.e., these
+    operators now implement short-circuit evaluation so the right operand is
+    evaluated only if the left operand does not suffice to determine the
+    result.
+
+  * Change `ScreenDetail` to a newtype and make `RationalRect` strict in its
+    contents.
+
+  * Added the `extensibleConf` field to `XConfig` which makes it easier for
+    contrib modules to have composable configuration (custom hooks, …).
+
+  * `util/GenerateManpage.hs` is no longer distributed in the tarball.
+    Instead, the manpage source is regenerated and manpage rebuilt
+    automatically in CI.
+
+  * `DestroyWindowEvent` is now broadcasted to layouts to let them know
+    window-specific resources can be discarded.
+
+## 0.15 (September 30, 2018)
+
+  * Reimplement `sendMessage` to deal properly with windowset changes made
+    during handling.
+
+  * Add new library functions `windowBracket` and `modifyWindowSet` to
+    `XMonad.Operations`.
+
+## 0.14.2 (August 21, 2018)
+
+### Bug Fixes
+
+  * Add the sample configuration file xmonad.hs again to the release tarball.
+    [https://github.com/xmonad/xmonad/issues/181]
 
 ## 0.14.1 (August 20, 2018)
 

CONFIG

@@ -1,82 +0,0 @@
-== Configuring xmonad ==
-
-xmonad is configured by creating and editing the file:
-
-    ~/.xmonad/xmonad.hs
-
-xmonad then uses settings from this file as arguments to the window manager,
-on startup. For a complete example of possible settings, see the file:
-
-    man/xmonad.hs
-
-Further examples are on the website, wiki and extension documentation.
-
-    http://haskell.org/haskellwiki/Xmonad
-
-== A simple example ==
-
-Here is a basic example, which overrides the default border width,
-default terminal, and some colours. This text goes in the file
-$HOME/.xmonad/xmonad.hs :
-
-    import XMonad
-
-    main = xmonad $ def
-        { borderWidth        = 2
-        , terminal           = "urxvt"
-        , normalBorderColor  = "#cccccc"
-        , focusedBorderColor = "#cd8b00" }
-
-You can find the defaults in the file:
-
-    XMonad/Config.hs
-
-== Checking your xmonad.hs is correct ==
-
-Place this text in ~/.xmonad/xmonad.hs, and then check that it is
-syntactically and type correct by loading it in the Haskell
-interpreter:
-
-    $ ghci ~/.xmonad/xmonad.hs
-    GHCi, version 6.8.1: http://www.haskell.org/ghc/  :? for help
-    Loading package base ... linking ... done.
-    Ok, modules loaded: Main.
-
-    Prelude Main> :t main
-    main :: IO ()
-
-Ok, looks good.
-
-== Loading your configuration ==
-
-To have xmonad start using your settings, type 'mod-q'.  xmonad will
-then load this new file, and run it.  If it is unable to, the defaults
-are used.
-
-To load successfully, both 'xmonad' and 'ghc' must be in your $PATH
-environment variable.  If GHC isn't in your path, for some reason, you
-can compile the xmonad.hs file yourself:
-
-    $ cd ~/.xmonad
-    $ ghc --make xmonad.hs
-    $ ls
-    xmonad    xmonad.hi xmonad.hs xmonad.o
-
-When you hit mod-q, this newly compiled xmonad will be used.
-
-== Where are the defaults? ==
-
-The default configuration values are defined in the source file:
-
-    XMonad/Config.hs
-
-the XConfig data structure itself is defined in:
-
-    XMonad/Core.hs
-
-== Extensions ==
-
-Since the xmonad.hs file is just another Haskell module, you may import
-and use any Haskell code or libraries you wish. For example, you can use
-things from the xmonad-contrib library, or other code you write
-yourself.

CONTRIBUTING.md

@@ -34,9 +34,15 @@ Awesome!  Here are a few things to keep in mind:
     nontrivial changes to xmonad.  There are a couple of ways you can
     chat with us:
 
+    - Join the [`#xmonad` IRC channel] on `irc.libera.chat` or the
+      official [matrix channel], which is linked to IRC.  This is the
+      preferred (and fastest!) way to get into contact with us.
+
     - Post a message to the [mailing list][ml].
 
-    - Join the `#xmonad` IRC channel on `chat.freenode.org`.
+  * [XMonad.Doc.Developing][xmonad-doc-developing] is a great
+    resource to get an overview of xmonad.  Make sure to also check
+    it if you want more details on the coding style.
 
   * Continue reading this document!
 
@@ -55,87 +61,71 @@ Here are some tips for getting your changes merged into xmonad:
   * Your changes should include relevant entries in the `CHANGES.md`
     file.  Help us communicate changes to the community.
 
-  * Make sure you test your changes using the [xmonad-testing][]
-    repository.  Include a new configuration file that shows off your
-    changes if possible by creating a PR on that repository as well.
+  * Make sure you test your changes against the most recent commit of
+    [xmonad][] (and [xmonad-contrib][], if you're contributing there).
+    If you're adding a new module or functionality, make sure to add an
+    example in the documentation and in the PR description.
 
-  * Make sure you read the section on rebasing and squashing commits
-    below.
+  * Make sure you run the automated tests.  Both [xmonad-contrib][]
+    and [xmonad][] have test-suites that you could run with
+    `stack test` for example.
 
-## Rebasing and Squashing Commits
+  * When committing, try to follow existing practices.  For more
+    information on what good commit messages look like, see [How to
+    Write a Git Commit Message][commit-cbeams] and the [Kernel
+    documentation][commit-kernel] about committing logical changes
+    separately.
 
-Under no circumstances should you ever merge the master branch into
-your feature branch.  This makes it nearly impossible to review your
-changes and we *will not accept your PR* if you do this.
+## Style Guidelines
 
-Instead of merging you should rebase your changes on top of the master
-branch.  If a core team member asks you to "rebase your changes" this
-is what they are talking about.
+Below are some common style guidelines that all of the core modules
+follow.  Before submitting a pull request, make sure that your code does
+as well!
 
-It's also helpful to squash all of your commits so that your pull
-request only contains a single commit.  Again, this makes it easier to
-review your changes and identify the changes later on in the Git
-history.
+  * Comment every top level function (particularly exported functions),
+    and provide a type signature; use Haddock syntax in the comments.
 
-### How to Rebase Your Changes
+  * Follow the coding style of the module that you are making changes to
+    (`n` spaces for indentation, where to break long type signatures, …).
 
-The goal of rebasing is to bring recent changes from the master branch
-into your feature branch.  This often helps resolve conflicts where
-you have changed a file that also changed in a recently merged pull
-request (i.e. the `CHANGES.md` file).  Here is how you do that.
+  * New code should not introduce any new warnings.  If you want to
+    check this yourself before submitting a pull request, there is the
+    `pedantic` flag, which is enforced in our CI.  You can enable it by
+    building your changes with `stack build --flag xmonad:pedantic` or
+    `cabal build --flag pedantic`.
 
-  1. Make sure that you have a `git remote` configured for the main
-     repository.  I like to call this remote `upstream`:
+  * Likewise, your code should be free of [hlint] warnings; this is also
+    enforced in our GitHub CI.
 
-        $ git remote add upstream https://github.com/xmonad/xmonad-contrib.git
+  * Partial functions are to be avoided: the window manager should not
+    crash, so do not call `error` or `undefined`.
 
-  2. Pull from upstream and rewrite your changes on top of master.  For
-     this to work you should not have any modified files in your
-     working directory.  Run these commands from within your feature
-     branch (the branch you are asking to be merged):
+  * Any pure function added to the core should have QuickCheck
+    properties precisely defining its behavior.
 
-        $ git fetch --all
-        $ git pull --rebase upstream master
+  * New modules should identify the author, and be submitted under the
+    same license as xmonad (BSD3 license).
 
-  3. If the rebase was successful you can now push your feature branch
-     back to GitHub.  You need to force the push since your commits
-     have been rewritten and have new IDs:
+## Keep rocking!
 
-        $ git push --force-with-lease
-
-  4. Your pull request should now be conflict-free and only contain the
-     changes that you actually made.
-
-### How to Squash Commits
-
-The goal of squashing commits is to produce a clean Git history where
-each pull request contains just one commit.
-
-  1. Use `git log` to see how many commits you are including in your
-     pull request.  (If you've already submitted your pull request you
-     can see this in the GitHub interface.)
-
-  2. Rebase all of those commits into a single commit.  Assuming you
-     want to squash the last four (4) commits into a single commit:
-
-        $ git rebase -i HEAD~4
-
-  3. Git will open your editor and display the commits you are
-     rebasing with the word "pick" in front of them.
-
-  4. Leave the first listed commit as "pick" and change the remaining
-     commits from "pick" to "squash".
-
-  5. Save the file and exit your editor.  Git will create a new commit
-     and open your editor so you can modify the commit message.
-
-  6. If everything was successful you can push your changed history
-     back up to GitHub:
-
-        $ git push --force-with-lease
+xmonad is a passion project created and maintained by the community.
+We'd love for you to maintain your own contributed modules (approve
+changes from other contributors, review code, etc.).  However, before
+we'd be comfortable adding you to the [xmonad GitHub
+organization][xmonad-gh-org] we need to trust that you have sufficient
+knowledge of Haskell and git; and have a way of chatting with you ([IRC,
+Matrix, etc.][community]).
 
+[hlint]: https://github.com/ndmitchell/hlint
 [xmonad]: https://github.com/xmonad/xmonad
 [xmonad-contrib]: https://github.com/xmonad/xmonad-contrib
 [xmonad-testing]: https://github.com/xmonad/xmonad-testing
 [x11]: https://github.com/xmonad/X11
 [ml]: https://mail.haskell.org/cgi-bin/mailman/listinfo/xmonad
+[xmonad-doc-developing]: https://xmonad.github.io/xmonad-docs/xmonad-contrib/XMonad-Doc-Developing.html
+[`#xmonad` IRC channel]: https://web.libera.chat/#xmonad
+[matrix channel]: https://matrix.to/#/#xmonad:matrix.org
+[commit-cbeams]: https://cbea.ms/git-commit/
+[commit-kernel]: https://www.kernel.org/doc/html/v4.10/process/submitting-patches.html#separate-your-changes
+[community]: https://xmonad.org/community.html
+[xmonad-gh-org]: https://github.com/xmonad

INSTALL.md

@@ -0,0 +1,402 @@
+# Install XMonad
+
+On many systems xmonad is available as a binary package in your
+distribution (Debian, Ubuntu, Fedora, Arch, Gentoo, …).
+It's by far the easiest way to get xmonad, although you'll miss out on the
+latest features and fixes that may not have been released yet.
+
+If you do want the latest and greatest, continue reading.
+Those who install from distro can skip this and go straight to
+[the XMonad Configuration Tutorial](TUTORIAL.md).
+
+<!-- https://github.com/frnmst/md-toc -->
+<!-- regenerate via: md_toc -s1 -p github INSTALL.md -->
+<!--TOC-->
+
+- [Dependencies](#dependencies)
+- [Preparation](#preparation)
+- [Download XMonad sources](#download-xmonad-sources)
+- [Build XMonad](#build-xmonad)
+  - [Build using Stack](#build-using-stack)
+  - [Build using cabal-install](#build-using-cabal-install)
+- [Make XMonad your window manager](#make-xmonad-your-window-manager)
+- [Custom Build Script](#custom-build-script)
+
+<!--TOC-->
+
+## Dependencies
+
+#### Debian, Ubuntu
+
+``` console
+$ sudo apt install \
+> git \
+> libx11-dev libxft-dev libxinerama-dev libxrandr-dev libxss-dev
+```
+
+#### Fedora
+
+``` console
+$ sudo dnf install \
+> git \
+> libX11-devel libXft-devel libXinerama-devel libXrandr-devel libXScrnSaver-devel
+```
+
+#### Arch
+
+``` console
+$ sudo pacman -S \
+> git \
+> xorg-server xorg-apps xorg-xinit xorg-xmessage \
+> libx11 libxft libxinerama libxrandr libxss \
+> pkgconf
+```
+
+#### Void
+
+``` console
+$ sudo xbps-install \
+> git \
+> ncurses-libtinfo-libs ncurses-libtinfo-devel \
+> libX11-devel libXft-devel libXinerama-devel libXrandr-devel libXScrnSaver-devel \
+> pkg-config
+```
+
+## Preparation
+
+We'll use the [XDG] directory specifications here, meaning our
+configuration will reside within `$XDG_CONFIG_HOME`, which is
+`~/.config` on most systems.  Let's create this directory and move to
+it:
+
+``` console
+$ mkdir -p ~/.config/xmonad && cd ~/.config/xmonad
+```
+
+If you already have an `xmonad.hs` configuration, you can copy it over
+now.  If not, you can use the defaults: create a file called `xmonad.hs`
+with the following content:
+
+``` haskell
+import XMonad
+
+main :: IO ()
+main = xmonad def
+```
+
+Older versions of xmonad used `~/.xmonad` instead.
+This is still supported, but XDG is preferred.
+
+## Download XMonad sources
+
+Still in `~/.config/xmonad`, clone `xmonad` and `xmonad-contrib` repositories
+using [git][]:
+
+``` console
+$ git clone https://github.com/xmonad/xmonad
+$ git clone https://github.com/xmonad/xmonad-contrib
+```
+
+This will give you the latest `HEAD`; if you want you can also check
+out a tagged release, e.g.:
+
+``` console
+$ git clone --branch v0.17.2 https://github.com/xmonad/xmonad
+$ git clone --branch v0.17.1 https://github.com/xmonad/xmonad-contrib
+```
+
+(Sources and binaries don't usually go into `~/.config`.  In our case,
+however, it avoids complexities related to Haskell build tools and lets us
+focus on the important bits of XMonad installation.)
+
+## Build XMonad
+
+There are two widely used Haskell build tools:
+
+* [Stack][stack]
+* [cabal-install][cabal-install]
+
+We include instructions for both.
+Unless you already know which one you prefer, use Stack, which is easier.
+
+### Build using Stack
+
+#### Install Stack
+
+Probably one of the best ways to get [stack] is to use [GHCup], which is the main Haskell installer according to language's official [website][GHCup] and community [survey]. GHCup is [widely available] and is considered less error prone than other installation options.
+
+You can also use your system's package
+manager:
+
+``` console
+$ sudo apt install haskell-stack    # Debian, Ubuntu
+$ sudo dnf install stack            # Fedora
+$ sudo pacman -S stack              # Arch
+```
+
+If you install stack via this method, it is advisable that you run
+`stack upgrade` after installation.  This will make sure that you are on
+the most recent version of the program, regardless of which version your
+distribution actually packages.
+
+If your distribution does not package stack, you can also easily install
+it via the following command (this is the recommended way to install
+stack via its [documentation][stack]):
+
+``` console
+$ curl -sSL https://get.haskellstack.org/ | sh
+```
+
+#### Create a New Project
+
+Let's create a stack project.  Since we're already in the correct
+directory (`~/.config/xmonad`) with `xmonad` and `xmonad-contrib`
+subdirectories, starting a new stack project is as simple as running `stack
+init`.
+
+Stack should now inform you that it will use the relevant `stack` and
+`cabal` files from `xmonad` and `xmonad-contrib` to generate its
+`stack.yaml` file.  At the time of writing, this looks a little bit like
+this:
+
+``` console
+$ stack init
+Looking for .cabal or package.yaml files to use to init the project.
+Using cabal packages:
+- xmonad-contrib/
+- xmonad/
+
+Selecting the best among 19 snapshots...
+
+* Matches https://raw.githubusercontent.com/commercialhaskell/stackage-snapshots/master/lts/17/9.yaml
+
+Selected resolver: https://raw.githubusercontent.com/commercialhaskell/stackage-snapshots/master/lts/17/9.yaml
+Initialising configuration using resolver: https://raw.githubusercontent.com/commercialhaskell/stackage-snapshots/master/lts/17/9.yaml
+Total number of user packages considered: 2
+Writing configuration to file: stack.yaml
+All done.
+```
+
+If you look into your current directory now, you should see a freshly
+generated `stack.yaml` file:
+
+``` console
+$ ls
+xmonad  xmonad-contrib  stack.yaml  xmonad.hs
+```
+
+The meat of that file (comments start with `#`, we've omitted them here)
+will look a little bit like
+
+``` yaml
+resolver:
+  url: https://raw.githubusercontent.com/commercialhaskell/stackage-snapshots/master/lts/17/9.yaml
+
+packages:
+- xmonad
+- xmonad-contrib
+```
+
+With `stack.yaml` alongside `xmonad.hs`, xmonad now knows that it needs to use
+`stack ghc` instead of just `ghc` when (re)compiling its configuration.
+If you want to keep xmonad sources and the stack project elsewhere, but still
+use `xmonad --recompile`, symlink your real `stack.yaml` into the xmonad
+configuration directory, or [use a custom build script](#custom-build-script).
+
+#### Install Everything
+
+Installing things is as easy as typing `stack install`.  This will
+install the correct version of GHC, as well as build all of the required
+packages (`stack build`) and then copy the relevant executables
+(`xmonad`, in our case) to `~/.local/bin`.  Make sure to add that
+directory to your `$PATH`!  The command `which xmonad` should now return
+that executable.  In case it does not, check if you still have xmonad
+installed via your package manager and uninstall it.
+
+If you're getting build failures while building the `X11` package it may
+be that you don't have the required C libraries installed.  See
+[above](#dependencies).
+
+### Build using cabal-install
+
+#### Install cabal-install
+
+Probably one of the best ways to get [cabal-install] is to use [GHCup], which is the main Haskell installer according to language's official [website][GHCup] and community [survey]. GHCup is [widely available] and is considered less error prone than other installation options.
+
+You can also use your system's package
+manager:
+
+``` console
+$ sudo apt install cabal-install    # Debian, Ubuntu
+$ sudo dnf install cabal-install    # Fedora
+$ sudo pacman -S cabal-install      # Arch
+```
+
+See also <https://www.haskell.org/cabal/#install-upgrade>.
+
+#### Create a New Project
+
+If you want to use `xmonad` or `xmonad-contrib` from git, you will need a
+`cabal.project` file. If you want to use both from [Hackage][], you should
+skip this step.
+
+Create a file named `cabal.project` containing:
+
+```
+packages: */*.cabal
+```
+
+(If you do this step without using [git] checkouts, you will get an error from
+cabal in the next step. Simply remove `cabal.project` and try again.)
+
+#### Install Everything
+
+You'll need to update the cabal package index, build xmonad and xmonad-contrib
+libraries and then build the xmonad binary:
+
+``` console
+$ cabal update
+$ cabal install --package-env=$HOME/.config/xmonad --lib base xmonad xmonad-contrib
+$ cabal install --package-env=$HOME/.config/xmonad xmonad
+```
+
+This will create a GHC environment in `~/.config/xmonad` so that the libraries
+are available for recompilation of the config file, and also install the
+xmonad binary to `~/.cabal/bin/xmonad`.  Make sure you have that directory in
+your `$PATH`!
+
+If you're getting build failures while building the `X11` package it may
+be that you don't have the required C libraries installed.  See
+[above](#dependencies).
+
+## Make XMonad your window manager
+
+This step varies depending on your distribution and X display manager (if
+any).
+
+#### Debian, Ubuntu
+
+`/etc/X11/xinit/xinitrc` runs `/etc/X11/Xsession` which runs `~/.xsession`, so
+you probably want to put `exec xmonad` there (don't forget the shebang and chmod).
+
+(Tested with `startx`, `xdm`, `lightdm`.)
+
+By using `~/.xsession`, the distro takes care of stuff like dbus, ssh-agent, X
+resources, etc.  If you want a completely manual X session, use `~/.xinitrc`
+instead.  Or invoke `startx`/`xinit` with an explicit path.
+
+Some newer display managers require an entry in `/usr/share/xsessions`.
+To use your custom `~/.xsession`, put these lines to
+`/usr/share/xsessions/default.desktop`:
+
+```
+[Desktop Entry]
+Name=Default X session
+Type=Application
+Exec=default
+```
+
+(Tested with `sddm`.)
+
+#### Fedora
+
+`/etc/X11/xinit/xinitrc` runs `~/.Xclients`, so you probably want to put `exec
+xmonad` there (don't forget the shebang and chmod).  Like in Debian, this can
+be overridden by having a completely custom `~/.xinitrc` or passing arguments
+to `startx`/`xinit`.
+
+X display managers (e.g. `lightdm`) usually invoke `/etc/X11/xinit/Xsession`
+instead, which additionally redirects output to `~/.xsession-errors` and also
+tries `~/.xsession` before `~/.Xclients`.
+
+Newer display managers require an entry in `/usr/share/xsessions`, which is
+available in the `xorg-x11-xinit-session` package.
+
+#### Arch
+
+`/etc/X11/xinit/xinitrc` runs `twm`, `xclock` and 3 `xterm`s; users are
+meant to just copy that to `~/.xinitrc` and
+[customize](https://wiki.archlinux.org/title/Xinit#xinitrc) it: replace the
+last few lines with `exec xmonad`.
+
+Display managers like `lightdm` have their own `Xsession` script which invokes
+`~/.xsession`.  Other display managers need an entry in
+`/usr/share/xsessions`, <https://aur.archlinux.org/packages/xinit-xsession/>
+provides one.
+
+#### See also
+
+* <https://xmonad.org/documentation.html#in-your-environment>
+* [FAQ: How can I use xmonad with a display manager? (xdm, kdm, gdm)](https://wiki.haskell.org/Xmonad/Frequently_asked_questions#How_can_I_use_xmonad_with_a_display_manager.3F_.28xdm.2C_kdm.2C_gdm.29)
+
+## Custom Build Script
+
+If you need to customize what happens during `xmonad --recompile` (bound to
+`M-q` by default), perhaps because your xmonad configuration is a whole
+separate Haskell package, you need to create a so-called `build` file.  This
+is quite literally just a shell script called `build` in your xmonad directory
+(which is `~/.config/xmonad` for us) that tells xmonad how it should build its
+executable.
+
+A good starting point (this is essentially [what xmonad would do][]
+without a build file, with the exception that we are invoking `stack
+ghc` instead of plain `ghc`) would be
+
+``` shell
+#!/bin/sh
+
+exec stack ghc --  \
+  --make xmonad.hs \
+  -i               \
+  -ilib            \
+  -fforce-recomp   \
+  -main-is main    \
+  -v0              \
+  -o "$1"
+```
+
+Don't forget to mark the file as `+x`: `chmod +x build`!
+
+Some example build scripts for `stack` and `cabal` are provided in the
+`xmonad-contrib` distribution. You can see those online in the
+[scripts/build][] directory. You might wish to use these if you have
+special dependencies for your `xmonad.hs`, especially with cabal as
+you must use a cabal file and often a `cabal.project` to specify them;
+`cabal install --lib` above generally isn't enough, and when it is
+it can be difficult to keep track of when you want to replicate your
+configuration on another system.
+
+#### Don't Recompile on Every Startup
+
+By default, xmonad always recompiles itself when a build script is used
+(because the build script could contain arbitrary code, so a simple
+check whether the `xmonad.hs` file changed is not enough).  If you find
+that too annoying, then you can use the `xmonad-ARCH` executable that
+`xmonad --recompile` generates instead of `xmonad` in your startup.  For
+example, instead of writing
+
+``` shell
+exec xmonad
+```
+
+in your `~/.xinitrc`, you would write
+
+``` shell
+exec $HOME/.cache/xmonad/xmonad-x86_64-linux
+```
+
+The `~/.cache` prefix is the `$XDG_CACHE_HOME` directory.  Note that
+if your xmonad configuration resides within `~/.xmonad`, then the
+executable will also be within that directory and not in
+`$XDG_CACHE_HOME`.
+
+[XDG]: https://specifications.freedesktop.org/basedir-spec/basedir-spec-latest.html
+[git]: https://git-scm.com/
+[stack]: https://docs.haskellstack.org/en/stable/README/
+[cabal-install]: https://www.haskell.org/cabal/
+[GHCup]: https://www.haskell.org/ghcup/
+[survey]: https://taylor.fausak.me/2022/11/18/haskell-survey-results/
+[widely available]: https://www.haskell.org/ghcup/install/#supported-platforms
+[what xmonad would do]: https://github.com/xmonad/xmonad/blob/master/src/XMonad/Core.hs#L659-L667
+[Hackage]: https://hackage.haskell.org/
+[scripts/build]: https://github.com/xmonad/xmonad-contrib/blob/master/scripts/build

LICENSE

@@ -1,31 +1,28 @@
 Copyright (c) 2007,2008 Spencer Janssen
 Copyright (c) 2007,2008 Don Stewart
+Copyright (c) The Xmonad Community. All rights reserved.
 
-All rights reserved.
+Redistribution and use in source and binary forms, with or without modification,
+are permitted provided that the following conditions are met:
 
-Redistribution and use in source and binary forms, with or without
-modification, are permitted provided that the following conditions
-are met:
+1. Redistributions of source code must retain the above copyright notice,
+this list of conditions and the following disclaimer.
 
-1. Redistributions of source code must retain the above copyright
-   notice, this list of conditions and the following disclaimer.
+2. Redistributions in binary form must reproduce the above copyright notice,
+this list of conditions and the following disclaimer in the documentation
+and/or other materials provided with the distribution.
 
-2. Redistributions in binary form must reproduce the above copyright
-   notice, this list of conditions and the following disclaimer in the
-   documentation and/or other materials provided with the distribution.
+3. Neither the name of the copyright holder nor the names of its contributors
+may be used to endorse or promote products derived from this software without
+specific prior written permission.
 
-3. Neither the name of the author nor the names of his contributors
-   may be used to endorse or promote products derived from this software
-   without specific prior written permission.
-
-THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
-IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
-WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
-DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE FOR
-ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
-DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
-OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
-HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
-STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
-ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
-POSSIBILITY OF SUCH DAMAGE.
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
+USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

MAINTAINERS.md

@@ -2,82 +2,145 @@
 
 ## The XMonad Core Team
 
-  * Adam Vogt [GitHub][aavogt]
-
-  * Brandon S Allbery [GitHub][geekosaur], IRC: `geekosaur`
+  * Brandon S Allbery [GitHub][geekosaur], IRC: `geekosaur`, [GPG][gpg:geekosaur]
 
   * Brent Yorgey [GitHub][byorgey], IRC: `byorgey`
 
-  * Daniel Wagner [GitHub][dmwit], IRC: `dmwit`
+  * Daniel Wagner [GitHub][dmwit], [Twitter][twitter:dmwit], IRC: `dmwit`
 
-  * David Lazar [GitHub][davidlazar]
+  * Sibi Prabakaran [GitHub][psibi], [Twitter][twitter:psibi], IRC: `sibi`
 
-  * Devin Mullins [GitHub][twifkak]
+  * Tomáš Janoušek [GitHub][liskin], [Twitter][twitter:liskin], IRC: `liskin`, [GPG][gpg:liskin]
 
-  * Peter J. Jones [GitHub][pjones], [Twitter][twitter:pjones], [OpenPGP Key][pgp:pjones], IRC: `pmade`
+  * Tony Zorman [GitHub][slotThe], IRC: `Solid`, [GPG][gpg:slotThe]
+
+[geekosaur]: https://github.com/geekosaur
+[byorgey]: https://github.com/byorgey
+[dmwit]: https://github.com/dmwit
+[psibi]: https://github.com/psibi
+[liskin]: https://github.com/liskin
+[slotThe]: https://github.com/slotThe
+
+[gpg:geekosaur]: https://github.com/geekosaur.gpg
+[gpg:liskin]: https://github.com/liskin.gpg
+[gpg:slotThe]: https://github.com/slotThe.gpg
+
+[twitter:dmwit]: https://twitter.com/dmwit13
+[twitter:psibi]: https://twitter.com/psibi
+[twitter:liskin]: https://twitter.com/Liskni_si
+
+## Hall of Fame (past maintainers/developers)
+
+  * Adam Vogt [GitHub](https://github.com/aavogt)
+
+  * Peter Simons [GitHub](https://github.com/peti), [Twitter](https://twitter.com/OriginalPeti)
+
+  * Spencer Janssen [GitHub](https://github.com/spencerjanssen)
+
+  * Don Stewart [GitHub](https://github.com/donsbot), [Twitter](https://twitter.com/donsbot)
+
+  * Jason Creighton [GitHub](https://github.com/JasonCreighton)
+
+  * David Roundy [GitHub](https://github.com/droundy)
+
+  * Daniel Schoepe [GitHub](https://github.com/dschoepe)
+
+  * Eric Mertens [GitHub](https://github.com/glguy)
+
+  * Nicolas Pouillard [GitHub](https://github.com/np)
+
+  * Roman Cheplyaka [GitHub](https://github.com/UnkindPartition)
+
+  * Gwern Branwen [GitHub](https://github.com/gwern)
+
+  * Lukas Mai [GitHub](https://github.com/mauke)
+
+  * Braden Shepherdson [GitHub](https://github.com/shepheb)
+
+  * Devin Mullins [GitHub](https://github.com/twifkak)
+
+  * David Lazar [GitHub](https://github.com/davidlazar)
+
+  * Peter J. Jones [GitHub](https://github.com/pjones)
 
 ## Release Procedures
 
-When the time comes to release another version of XMonad and Contrib...
+When the time comes to release another version of xmonad and xmonad-contrib:
 
-  1. Create a release branch (e.g., `release-0.XX`).
+  1. Update the version number in all the `*.cabal` files and let the CI
+     verify that it all builds together.
 
-     This will allow you to separate the release process from main
-     development.  Changes you make on this branch will be merged back
-     into `master` as one of the last steps.
+  2. Review documentation files and make sure they are accurate:
 
-  2. Update the version number in the `*.cabal` files and verify
-     dependencies and documentation.  This includes the `tested-with:`
-     field.
+     - [`README.md`](README.md)
+     - [`CHANGES.md`](CHANGES.md) (bump version, set date)
+     - [`INSTALL.md`](INSTALL.md)
+     - [`man/xmonad.1.markdown.in`](man/xmonad.1.markdown.in)
+     - [haddocks](https://xmonad.github.io/xmonad-docs/)
 
-  3. Use the [packdeps][] tool to ensure you have the dependency
-     versions correct.  If you need to update the version of a
-     dependency then you should rebuild and retest.
+     If the manpage changes, wait for the CI to rebuild the rendered outputs.
 
-  4. Review documentation files and make sure they are accurate:
+  3. Update the website:
 
-     - `README.md`
-     - `CHANGES.md`
-     - and the `example-config.hs` in the `xmonad-testing` repo
+     - Draft a [new release announcement][web-announce].
+     - Check install instructions, guided tour, keybindings cheat sheet, …
 
-  5. Generate the manpage:
+  4. Make sure that `tested-with:` covers several recent releases of GHC, that
+     `.github/workflows/haskell-ci.yml` had been updated to test all these GHC
+     versions and that `.github/workflows/stack.yml` tests with several recent
+     revisions of [Stackage][] LTS.
 
-     * `cabal configure` with the `-fgeneratemanpage` flag
-     * Build the project
-     * Run the `generatemanpage` tool from the top level of this repo
-     * Review the man page: `man -l man/xmonad.1`
+  5. Trigger the Haskell-CI workflow and fill in the candidate version number.
+     This will upload a release candidate to Hackage.
 
-  6. Tag the repository with the release version (e.g., `v0.13`)
+     - https://github.com/xmonad/xmonad/actions/workflows/haskell-ci.yml
+     - https://github.com/xmonad/xmonad-contrib/actions/workflows/haskell-ci.yml
 
-  7. Build the project tarballs (`cabal sdist`)
+     Check that everything looks good. If not, push fixes and do another
+     candidate. When everything's ready, create a release on GitHub:
 
-  8. Upload the packages to Hackage (`cabal upload`)
+     - https://github.com/xmonad/xmonad/releases/new
+     - https://github.com/xmonad/xmonad-contrib/releases/new
 
-  9. Merge the release branches into `master`
+     CI will automatically upload the final release to Hackage.
 
-  10. Update the website:
+     See [haskell-ci-hackage.patch][] for details about the Hackage automation.
 
-      * Generate and push haddocks with `xmonad-web/gen-docs.sh`
+  6. Post announcement to:
 
-      * Check that `tour.html` and `intro.html` are up to date, and
-        mention all core bindings
+     - [xmonad.org website](https://github.com/xmonad/xmonad-web/tree/gh-pages/news/_posts)
+     - [XMonad mailing list](https://mail.haskell.org/mailman/listinfo/xmonad)
+     - [Haskell Cafe](https://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe)
+     - [Haskell Discourse](https://discourse.haskell.org/)
+     - [Twitter](https://twitter.com/xmonad)
+     - [Reddit](https://www.reddit.com/r/xmonad/)
 
-  11. Update the topic for the IRC channel (`#xmonad`)
+     See [old announcements][old-announce] ([even older][older-announce]) for inspiration.
 
-  12. Send the `announce-0.XX.txt` file to:
+  7. Trigger xmonad-docs build to generate and persist docs for the just
+     released version:
 
-      - XMonad mailing list
-      - Haskell Cafe
+     - https://github.com/xmonad/xmonad-docs/actions/workflows/stack.yml
 
-[packdeps]: http://hackage.haskell.org/package/packdeps
+  8. Bump version for development (add `.9`) and prepare fresh sections in
+     [`CHANGES.md`](CHANGES.md).
 
-[aavogt]: https://github.com/orgs/xmonad/people/aavogt
-[geekosaur]: https://github.com/orgs/xmonad/people/geekosaur
-[byorgey]: https://github.com/orgs/xmonad/people/byorgey
-[dmwit]: https://github.com/orgs/xmonad/people/dmwit
-[davidlazar]: https://github.com/orgs/xmonad/people/davidlazar
-[twifkak]: https://github.com/orgs/xmonad/people/twifkak
+[packdeps]: https://hackage.haskell.org/package/packdeps
+[Stackage]: https://www.stackage.org/
+[haskell-ci-hackage.patch]: .github/workflows/haskell-ci-hackage.patch
+[web-announce]: https://github.com/xmonad/xmonad-web/tree/gh-pages/news/_posts
+[old-announce]: https://github.com/xmonad/xmonad-web/blob/gh-pages/news/_posts/2021-10-27-xmonad-0-17-0.md
+[older-announce]: https://github.com/xmonad/xmonad-web/tree/55614349421ebafaef4a47424fcb16efa80ff768
 
-[pjones]: https://github.com/orgs/xmonad/people/pjones
-[twitter:pjones]: https://twitter.com/contextualdev
-[pgp:pjones]: http://pgp.mit.edu/pks/lookup?op=get&search=0x526722D1204284CB
+## Website and Other Accounts
+
+* The [xmonad twitter] is tended to by [liskin].
+
+* The [xmonad.org] domain is owned by [eyenx] and the website itself is
+  deployed via GitHub Pages.  It can be updated by making a pull request
+  against the [xmonad-web] repository.
+
+[eyenx]: https://github.com/eyenx
+[xmonad-web]: https://github.com/xmonad/xmonad-web/
+[xmonad.org]: https://xmonad.org/
+[xmonad twitter]: https://twitter.com/xmonad

README.md

@@ -1,8 +1,27 @@
-# xmonad: A Tiling Window Manager
+<p align="center">
+  <a href="https://xmonad.org/"><img alt="XMonad logo" src="https://xmonad.org/images/logo-wrapped.svg" height=150></a>
+</p>
+<p align="center">
+  <a href="https://hackage.haskell.org/package/xmonad"><img alt="Hackage" src="https://img.shields.io/hackage/v/xmonad?logo=haskell"></a>
+  <a href="https://github.com/xmonad/xmonad/blob/readme/LICENSE"><img alt="License" src="https://img.shields.io/github/license/xmonad/xmonad"></a>
+  <a href="https://haskell.org/"><img alt="Made in Haskell" src="https://img.shields.io/badge/Made%20in-Haskell-%235e5086?logo=haskell"></a>
+  <br>
+  <a href="https://github.com/xmonad/xmonad/actions/workflows/stack.yml"><img alt="Stack" src="https://img.shields.io/github/actions/workflow/status/xmonad/xmonad/stack.yml?label=Stack&logo=githubactions&logoColor=white"></a>
+  <a href="https://github.com/xmonad/xmonad/actions/workflows/haskell-ci.yml"><img alt="Cabal" src="https://img.shields.io/github/actions/workflow/status/xmonad/xmonad/haskell-ci.yml?label=Cabal&logo=githubactions&logoColor=white"></a>
+  <a href="https://github.com/xmonad/xmonad/actions/workflows/nix.yml"><img alt="Nix" src="https://img.shields.io/github/actions/workflow/status/xmonad/xmonad/nix.yml?label=Nix&logo=githubactions&logoColor=white"></a>
+  <br>
+  <a href="https://github.com/sponsors/xmonad"><img alt="GitHub Sponsors" src="https://img.shields.io/github/sponsors/xmonad?label=GitHub%20Sponsors&logo=githubsponsors"></a>
+  <a href="https://opencollective.com/xmonad"><img alt="Open Collective" src="https://img.shields.io/opencollective/all/xmonad?label=Open%20Collective&logo=opencollective"></a>
+  <br>
+  <a href="https://web.libera.chat/#xmonad"><img alt="Chat on #xmonad@irc.libera.chat" src="https://img.shields.io/badge/%23%20chat-on%20libera-brightgreen"></a>
+  <a href="https://matrix.to/#/#xmonad:matrix.org"><img alt="Chat on #xmonad:matrix.org" src="https://img.shields.io/matrix/xmonad:matrix.org?logo=matrix"></a>
+</p>
 
-[![Build Status](https://travis-ci.org/xmonad/xmonad.svg?branch=master)](https://travis-ci.org/xmonad/xmonad)
+# xmonad
 
-[xmonad][] is a tiling window manager for X. Windows are arranged
+**A tiling window manager for X11.**
+
+[XMonad][web:xmonad] is a tiling window manager for X11. Windows are arranged
 automatically to tile the screen without gaps or overlap, maximising
 screen use. Window manager features are accessible from the keyboard:
 a mouse is optional. xmonad is written, configured and extensible in
@@ -12,118 +31,74 @@ dynamically, and different layouts may be used on each
 workspace. Xinerama is fully supported, allowing windows to be tiled
 on several physical screens.
 
-## Quick Start
+This repository contains the [xmonad][hackage:xmonad] package, a minimal,
+stable, yet extensible core. It is accompanied by
+[xmonad-contrib][gh:xmonad-contrib], a library of hundreds of additional
+community-maintained tiling algorithms and extension modules. The two combined
+make for a powerful X11 window-manager with endless customization
+possibilities. They are, quite literally, libraries for creating your own
+window manager.
 
-  * From hackage:
+## Installation
 
-        cabal update
-        cabal install xmonad xmonad-contrib
+For installation and configuration instructions, please see:
 
-  * Alternatively, build from source using the following repositories:
+ * [downloading and installing xmonad][web:download]
+ * [installing latest xmonad snapshot from git][web:install]
+ * [configuring xmonad][web:tutorial]
 
-    - <https://github.com/xmonad/xmonad>
+If you run into any trouble, consult our [documentation][web:documentation] or
+ask the [community][web:community] for help.
 
-    - <https://github.com/xmonad/xmonad-contrib>
+## Contributing
 
-For the full story, read on.
+We welcome all forms of contributions:
 
-## Building
+ * [bug reports and feature ideas][gh:xmonad:issues]
+   (also to [xmonad-contrib][gh:xmonad-contrib:issues])
+ * [bug fixes, new features, new extensions][gh:xmonad:pulls]
+   (usually to [xmonad-contrib][gh:xmonad-contrib:pulls])
+ * documentation fixes and improvements: [xmonad][gh:xmonad],
+   [xmonad-contrib][gh:xmonad-contrib], [xmonad-web][gh:xmonad-web]
+ * helping others in the [community][web:community]
+ * financial support: [GitHub Sponsors][gh:xmonad:sponsors],
+   [Open Collective][opencollective:xmonad]
 
-Building is quite straightforward, and requires a basic Haskell toolchain.
-On many systems xmonad is available as a binary package in your
-package system (e.g. on Debian or Gentoo). If at all possible, use this
-in preference to a source build, as the dependency resolution will be
-simpler.
-
-We'll now walk through the complete list of toolchain dependencies.
-
-  * GHC: the Glasgow Haskell Compiler
-
-    You first need a Haskell compiler. Your distribution's package
-    system will have binaries of GHC (the Glasgow Haskell Compiler),
-    the compiler we use, so install that first. If your operating
-    system's package system doesn't provide a binary version of GHC
-    and the `cabal-install` tool, you can install both using the
-    [Haskell Platform][platform].
-
-    It shouldn't be necessary to compile GHC from source -- every common
-    system has a pre-build binary version.  However, if you want to
-    build from source, the following links will be helpful:
-
-      - GHC: <http://haskell.org/ghc/>
-
-      - Cabal: <http://haskell.org/cabal/download.html>
-
-  * X11 libraries:
-
-    Since you're building an X application, you'll need the C X11
-    library headers. On many platforms, these come pre-installed. For
-    others, such as Debian, you can get them from your package manager:
-
-        # for xmonad
-        $ apt-get install libx11-dev libxinerama-dev libxext-dev libxrandr-dev libxss-dev
-
-        # for xmonad-contrib
-        $ apt-get install libxft-dev
-
-Then build and install with:
-
-    $ cabal install
-
-## Running xmonad
-
-If you built XMonad using `cabal` then add:
-
-    exec $HOME/.cabal/bin/xmonad
-
-to the last line of your `.xsession` or `.xinitrc` file.
-
-## Configuring
-
-See the [CONFIG][] document and the [example configuration file][example-config].
-
-## XMonadContrib
-
-There are many extensions to xmonad available in the XMonadContrib
-(xmc) library. Examples include an ion3-like tabbed layout, a
-prompt/program launcher, and various other useful modules.
-XMonadContrib is available at:
-
-  * Latest release: <http://hackage.haskell.org/package/xmonad-contrib>
-
-  * Git version: <https://github.com/xmonad/xmonad-contrib>
-
-## Other Useful Programs
-
-A nicer xterm replacement, that supports resizing better:
-
-  * urxvt: <http://software.schmorp.de/pkg/rxvt-unicode.html>
-
-For custom status bars:
-
-  * xmobar: <http://hackage.haskell.org/package/xmobar>
-
-  * taffybar: <https://github.com/travitch/taffybar>
-
-  * dzen: <http://gotmor.googlepages.com/dzen>
-
-For a program dispatch menu:
-
-  * [XMonad.Prompt.Shell][xmc-prompt-shell]: (from [XMonadContrib][])
-
-  * dmenu: <http://www.suckless.org/download/>
-
-  * gmrun: (in your package system)
+Please do read the [CONTRIBUTING][gh:xmonad:contributing] document for more
+information about bug reporting and code contributions. For a brief overview
+of the architecture and code conventions, see the [documentation for the
+`XMonad.Doc.Developing` module][doc:developing]. If in doubt, [talk to
+us][web:community].
 
 ## Authors
 
-  * Spencer Janssen
-  * Don Stewart
-  * Jason Creighton
+Started in 2007 by [Spencer Janssen][gh:spencerjanssen], [Don
+Stewart][gh:donsbot] and [Jason Creighton][gh:JasonCreighton], the
+[XMonad][web:xmonad] project lives on thanks to [new generations of
+maintainers][gh:xmonad:maintainers] and [dozens of
+contributors][gh:xmonad:contributors].
 
-[xmonad]: http://xmonad.org
-[xmonadcontrib]: https://hackage.haskell.org/package/xmonad-contrib
-[xmc-prompt-shell]: https://hackage.haskell.org/package/xmonad-contrib/docs/XMonad-Prompt-Shell.html
-[platform]: http://haskell.org/platform/
-[example-config]: https://github.com/xmonad/xmonad-testing/blob/master/example-config.hs
-[config]: https://github.com/xmonad/xmonad/blob/master/CONFIG
+[gh:spencerjanssen]: https://github.com/spencerjanssen
+[gh:donsbot]: https://github.com/donsbot
+[gh:JasonCreighton]: https://github.com/JasonCreighton
+
+[doc:developing]: https://xmonad.github.io/xmonad-docs/xmonad-contrib/XMonad-Doc-Developing.html
+[gh:xmonad-contrib:issues]: https://github.com/xmonad/xmonad-contrib/issues
+[gh:xmonad-contrib:pulls]: https://github.com/xmonad/xmonad-contrib/pulls
+[gh:xmonad-contrib]: https://github.com/xmonad/xmonad-contrib
+[gh:xmonad-web]: https://github.com/xmonad/xmonad-web
+[gh:xmonad:contributing]: https://github.com/xmonad/xmonad/blob/master/CONTRIBUTING.md
+[gh:xmonad:contributors]: https://github.com/xmonad/xmonad/graphs/contributors
+[gh:xmonad:issues]: https://github.com/xmonad/xmonad/issues
+[gh:xmonad:maintainers]: https://github.com/xmonad/xmonad/blob/master/MAINTAINERS.md
+[gh:xmonad:pulls]: https://github.com/xmonad/xmonad/pulls
+[gh:xmonad:sponsors]: https://github.com/sponsors/xmonad
+[gh:xmonad]: https://github.com/xmonad/xmonad
+[hackage:xmonad]: https://hackage.haskell.org/package/xmonad
+[opencollective:xmonad]: https://opencollective.com/xmonad
+[web:community]: https://xmonad.org/community.html
+[web:documentation]: https://xmonad.org/documentation.html
+[web:download]: https://xmonad.org/download.html
+[web:install]: https://xmonad.org/INSTALL.html
+[web:tutorial]: https://xmonad.org/TUTORIAL.html
+[web:xmonad]: https://xmonad.org/

STYLE

@@ -1,22 +0,0 @@
-
-== Coding guidelines for contributing to
-== xmonad and the xmonad contributed extensions
-
-* Comment every top level function (particularly exported functions), and
-  provide a type signature; use Haddock syntax in the comments.
-
-* Follow the coding style of the other modules.
-
-* Code should be compilable with -Wall -Werror -fno-warn-unused-do-bind -fwarn-tabs.
-  There should be no warnings.
-
-* Partial functions should be avoided: the window manager should not
-  crash, so do not call `error` or `undefined`
-
-* Use 4 spaces for indenting.
-
-* Any pure function added to the core should have QuickCheck properties
-  precisely defining its behavior.
-
-* New modules should identify the author, and be submitted under
-  the same license as xmonad (BSD3 license or freer).

cabal.haskell-ci

@@ -0,0 +1,17 @@
+apt:
+  libx11-dev
+  libxext-dev
+  libxinerama-dev
+  libxrandr-dev
+  libxss-dev
+
+github-patches:
+  .github/workflows/haskell-ci-hackage.patch
+
+raw-project
+  optimization: False
+  package xmonad
+    flags: +pedantic
+
+-- avoid --haddock-all which overwrites *-docs.tar.gz with tests docs
+haddock-components: libs

cabal.project

@@ -1 +1,4 @@
-packages: ./
+-- cabal.project
+
+packages:
+  xmonad.cabal

flake.nix

@@ -0,0 +1,106 @@
+# This file is maintained by @IvanMalison and @LSLeary (github)
+# See xmonad-contrib/NIX.md for an overview of module usage.
+{
+  inputs = {
+    flake-utils.url = github:numtide/flake-utils;
+    git-ignore-nix.url = github:hercules-ci/gitignore.nix/master;
+    unstable.url = github:NixOS/nixpkgs/nixos-unstable;
+  };
+  outputs = { self, flake-utils, nixpkgs, unstable, git-ignore-nix }:
+  let
+    hpath = { prefix ? null, compiler ? null }:
+      (if prefix == null then [] else [ prefix ]) ++
+      (if compiler == null
+       then [ "haskellPackages" ]
+       else [ "haskell" "packages" compiler ]
+      );
+    fromHOL = hol: comp: final: prev: with prev.lib; with attrsets;
+      let
+        path   = hpath comp;
+        root   = head path;
+        branch = tail path;
+        hpkgs' = (getAttrFromPath path prev).override (old: {
+          overrides = composeExtensions (old.overrides or (_: _: {}))
+            (hol final prev);
+        });
+      in {
+        ${root} = recursiveUpdate prev.${root} (setAttrByPath branch hpkgs');
+      };
+    hoverlay = final: prev: hself: hsuper:
+      with prev.haskell.lib.compose; {
+        xmonad = hself.callCabal2nix "xmonad"
+          (git-ignore-nix.lib.gitignoreSource ./.) { };
+      };
+    defComp = if builtins.pathExists ./comp.nix
+      then import ./comp.nix
+      else { };
+    overlay = fromHOL hoverlay defComp;
+    overlays = [ overlay ];
+    nixosModule = { config, pkgs, lib, ... }: with lib; with attrsets;
+      let
+        cfg = config.services.xserver.windowManager.xmonad.flake;
+        comp = { inherit (cfg) prefix compiler; };
+      in {
+        options = {
+          services.xserver.windowManager.xmonad.flake = with types; {
+            enable = mkEnableOption "flake";
+            prefix = mkOption {
+              default = null;
+              type = nullOr string;
+              example = literalExpression "\"unstable\"";
+              description = ''
+                Specify a nested alternative <literal>pkgs</literal> by attrName.
+              '';
+            };
+            compiler = mkOption {
+              default = null;
+              type = nullOr string;
+              example = literalExpression "\"ghc922\"";
+              description = ''
+                Which compiler to build xmonad with.
+                Must be an attribute of <literal>pkgs.haskell.packages</literal>.
+                Sets <option>xmonad.haskellPackages</option> to match.
+              '';
+            };
+          };
+        };
+        config = mkIf cfg.enable {
+          nixpkgs.overlays = [ (fromHOL hoverlay comp) ];
+          services.xserver.windowManager.xmonad.haskellPackages =
+            getAttrFromPath (hpath comp) pkgs;
+        };
+      };
+    nixosModules = [ nixosModule ];
+  in flake-utils.lib.eachDefaultSystem (system:
+  let pkgs = import nixpkgs { inherit system overlays; };
+      hpkg = pkgs.lib.attrsets.getAttrFromPath (hpath defComp) pkgs;
+      modifyDevShell =
+        if builtins.pathExists ./develop.nix
+        then import ./develop.nix
+        else _: x: x;
+  in
+  rec {
+    devShell = hpkg.shellFor (modifyDevShell pkgs {
+      packages = p: [ p.xmonad ];
+    });
+    defaultPackage = hpkg.xmonad;
+    # An auxiliary NixOS module that modernises the standard xmonad NixOS module
+    # and wrapper script used, replacing them with versions from unstable.
+    # Currently, due to the NIX_GHC --> XMONAD_GHC env var change, this is
+    # necessary in order for Mod-q recompilation to work out-of-the-box.
+    modernise =
+      let
+        xmonadModFile = "services/x11/window-managers/xmonad.nix";
+        unpkgs = import unstable { inherit system; };
+        replaceWrapper = _: _:
+          { xmonad-with-packages = unpkgs.xmonad-with-packages; };
+      in {
+        disabledModules = [ xmonadModFile ];
+        imports = [ (unstable + "/nixos/modules/" + xmonadModFile) ];
+        nixpkgs.overlays = [ replaceWrapper ];
+      };
+  }) // {
+    inherit hoverlay overlay overlays nixosModule nixosModules;
+    lib = { inherit hpath fromHOL; };
+  };
+}

man/Makefile

@@ -0,0 +1,11 @@
+.PHONY: all
+all: xmonad.1 xmonad.1.html
+
+xmonad.1.markdown: xmonad.1.markdown.in
+	(cd .. && util/GenerateManpage.hs) <$< >$@
+
+xmonad.1: xmonad.1.markdown
+	pandoc --from=markdown --to=man --standalone --output=$@ $<
+
+xmonad.1.html: xmonad.1.markdown
+	pandoc --from=markdown --to=html --standalone --table-of-contents --output=$@ $<

man/xmonad.1

@@ -1,13 +1,13 @@
-.\" Automatically generated by Pandoc 2.2.1
+.\" Automatically generated by Pandoc 2.9.2.1
 .\"
-.TH "XMONAD" "1" "20 August 2018" "Tiling Window Manager" ""
+.TH "XMONAD" "1" "27 October 2021" "Tiling Window Manager" ""
 .hy
 .SH Name
 .PP
-xmonad \- Tiling Window Manager
+xmonad - Tiling Window Manager
 .SH Description
 .PP
-\f[I]xmonad\f[] is a minimalist tiling window manager for X, written in
+\f[I]xmonad\f[R] is a minimalist tiling window manager for X, written in
 Haskell.
 Windows are managed using automatic layout algorithms, which can be
 dynamically reconfigured.
@@ -15,14 +15,14 @@ At any time windows are arranged so as to maximize the use of screen
 real estate.
 All features of the window manager are accessible purely from the
 keyboard: a mouse is entirely optional.
-\f[I]xmonad\f[] is configured in Haskell, and custom layout algorithms
+\f[I]xmonad\f[R] is configured in Haskell, and custom layout algorithms
 may be implemented by the user in config files.
-A principle of \f[I]xmonad\f[] is predictability: the user should know
+A principle of \f[I]xmonad\f[R] is predictability: the user should know
 in advance precisely the window arrangement that will result from any
 action.
 .PP
-By default, \f[I]xmonad\f[] provides three layout algorithms: tall, wide
-and fullscreen.
+By default, \f[I]xmonad\f[R] provides three layout algorithms: tall,
+wide and fullscreen.
 In tall or wide mode, windows are tiled and arranged to prevent overlap
 and maximize screen use.
 Sets of windows are grouped together on virtual screens, and each screen
@@ -31,34 +31,34 @@ Multiple physical monitors are supported via Xinerama, allowing
 simultaneous display of a number of screens.
 .PP
 By utilizing the expressivity of a modern functional language with a
-rich static type system, \f[I]xmonad\f[] provides a complete, featureful
-window manager in less than 1200 lines of code, with an emphasis on
-correctness and robustness.
+rich static type system, \f[I]xmonad\f[R] provides a complete,
+featureful window manager in less than 1200 lines of code, with an
+emphasis on correctness and robustness.
 Internal properties of the window manager are checked using a
 combination of static guarantees provided by the type system, and
-type\-based automated testing.
+type-based automated testing.
 A benefit of this is that the code is simple to understand, and easy to
 modify.
 .SH Usage
 .PP
-\f[I]xmonad\f[] places each window into a \[lq]workspace\[rq].
+\f[I]xmonad\f[R] places each window into a \[lq]workspace\[rq].
 Each workspace can have any number of windows, which you can cycle
-though with mod\-j and mod\-k.
+though with mod-j and mod-k.
 Windows are either displayed full screen, tiled horizontally, or tiled
 vertically.
-You can toggle the layout mode with mod\-space, which will cycle through
+You can toggle the layout mode with mod-space, which will cycle through
 the available modes.
 .PP
-You can switch to workspace N with mod\-N.
-For example, to switch to workspace 5, you would press mod\-5.
+You can switch to workspace N with mod-N.
+For example, to switch to workspace 5, you would press mod-5.
 Similarly, you can move the current window to another workspace with
-mod\-shift\-N.
+mod-shift-N.
 .PP
 When running with multiple monitors (Xinerama), each screen has exactly
 1 workspace visible.
-mod\-{w,e,r} switch the focus between screens, while shift\-mod\-{w,e,r}
+mod-{w,e,r} switch the focus between screens, while shift-mod-{w,e,r}
 move the current window to that screen.
-When \f[I]xmonad\f[] starts, workspace 1 is on screen 1, workspace 2 is
+When \f[I]xmonad\f[R] starts, workspace 1 is on screen 1, workspace 2 is
 on screen 2, etc.
 When switching workspaces to one that is already visible, the current
 and visible workspaces are swapped.
@@ -67,221 +67,159 @@ and visible workspaces are swapped.
 xmonad has several flags which you may pass to the executable.
 These flags are:
 .TP
-.B \[en]recompile
-Recompiles your configuration in \f[I]~/.xmonad/xmonad.hs\f[]
-.RS
-.RE
+\[en]recompile
+Recompiles your \f[I]xmonad.hs\f[R] configuration
 .TP
-.B \[en]restart
-Causes the currently running \f[I]xmonad\f[] process to restart
-.RS
-.RE
+\[en]restart
+Causes the currently running \f[I]xmonad\f[R] process to restart
 .TP
-.B \[en]replace
+\[en]replace
 Replace the current window manager with xmonad
-.RS
-.RE
 .TP
-.B \[en]version
-Display version of \f[I]xmonad\f[]
-.RS
-.RE
+\[en]version
+Display version of \f[I]xmonad\f[R]
 .TP
-.B \[en]verbose\-version
-Display detailed version of \f[I]xmonad\f[]
-.RS
-.RE
-.PP
-##Default keyboard bindings
+\[en]verbose-version
+Display detailed version of \f[I]xmonad\f[R]
+.SS Default keyboard bindings
 .TP
-.B mod\-shift\-return
+mod-shift-return
 Launch terminal
-.RS
-.RE
 .TP
-.B mod\-p
+mod-p
 Launch dmenu
-.RS
-.RE
 .TP
-.B mod\-shift\-p
+mod-shift-p
 Launch gmrun
-.RS
-.RE
 .TP
-.B mod\-shift\-c
+mod-shift-c
 Close the focused window
-.RS
-.RE
 .TP
-.B mod\-space
+mod-space
 Rotate through the available layout algorithms
-.RS
-.RE
 .TP
-.B mod\-shift\-space
+mod-shift-space
 Reset the layouts on the current workspace to default
-.RS
-.RE
 .TP
-.B mod\-n
+mod-n
 Resize viewed windows to the correct size
-.RS
-.RE
 .TP
-.B mod\-tab
+mod-tab
 Move focus to the next window
-.RS
-.RE
 .TP
-.B mod\-shift\-tab
+mod-shift-tab
 Move focus to the previous window
-.RS
-.RE
 .TP
-.B mod\-j
+mod-j
 Move focus to the next window
-.RS
-.RE
 .TP
-.B mod\-k
+mod-k
 Move focus to the previous window
-.RS
-.RE
 .TP
-.B mod\-m
+mod-m
 Move focus to the master window
-.RS
-.RE
 .TP
-.B mod\-return
+mod-return
 Swap the focused window and the master window
-.RS
-.RE
 .TP
-.B mod\-shift\-j
+mod-shift-j
 Swap the focused window with the next window
-.RS
-.RE
 .TP
-.B mod\-shift\-k
+mod-shift-k
 Swap the focused window with the previous window
-.RS
-.RE
 .TP
-.B mod\-h
+mod-h
 Shrink the master area
-.RS
-.RE
 .TP
-.B mod\-l
+mod-l
 Expand the master area
-.RS
-.RE
 .TP
-.B mod\-t
+mod-t
 Push window back into tiling
-.RS
-.RE
 .TP
-.B mod\-comma
+mod-comma
 Increment the number of windows in the master area
-.RS
-.RE
 .TP
-.B mod\-period
+mod-period
 Deincrement the number of windows in the master area
-.RS
-.RE
 .TP
-.B mod\-shift\-q
+mod-shift-q
 Quit xmonad
-.RS
-.RE
 .TP
-.B mod\-q
+mod-q
 Restart xmonad
-.RS
-.RE
 .TP
-.B mod\-shift\-slash
+mod-shift-slash
 Run xmessage with a summary of the default keybindings (useful for
 beginners)
-.RS
-.RE
 .TP
-.B mod\-question
+mod-question
 Run xmessage with a summary of the default keybindings (useful for
 beginners)
-.RS
-.RE
 .TP
-.B mod\-[1..9]
+mod-[1..9]
 Switch to workspace N
-.RS
-.RE
 .TP
-.B mod\-shift\-[1..9]
+mod-shift-[1..9]
 Move client to workspace N
-.RS
-.RE
 .TP
-.B mod\-{w,e,r}
+mod-{w,e,r}
 Switch to physical/Xinerama screens 1, 2, or 3
-.RS
-.RE
 .TP
-.B mod\-shift\-{w,e,r}
+mod-shift-{w,e,r}
 Move client to screen 1, 2, or 3
-.RS
-.RE
 .TP
-.B mod\-button1
+mod-button1
 Set the window to floating mode and move by dragging
-.RS
-.RE
 .TP
-.B mod\-button2
+mod-button2
 Raise the window to the top of the stack
-.RS
-.RE
 .TP
-.B mod\-button3
+mod-button3
 Set the window to floating mode and resize by dragging
-.RS
-.RE
 .SH Examples
 .PP
-To use xmonad as your window manager add to your \f[I]~/.xinitrc\f[]
-file:
+To use xmonad as your window manager add to your
+\f[I]\[ti]/.xinitrc\f[R] file:
 .RS
 .PP
 exec xmonad
 .RE
 .SH Customization
 .PP
-xmonad is customized in ~/.xmonad/xmonad.hs, and then restarted with
-mod\-q.
+xmonad is customized in your \f[I]xmonad.hs\f[R], and then restarted
+with mod-q.
+You can choose where your configuration file lives by
+.IP "1." 3
+Setting \f[C]XMONAD_DATA_DIR,\f[R] \f[C]XMONAD_CONFIG_DIR\f[R], and
+\f[C]XMONAD_CACHE_DIR\f[R]; \f[I]xmonad.hs\f[R] is then expected to be
+in \f[C]XMONAD_CONFIG_DIR\f[R].
+.IP "2." 3
+Creating \f[I]xmonad.hs\f[R] in \f[I]\[ti]/.xmonad\f[R].
+.IP "3." 3
+Creating \f[I]xmonad.hs\f[R] in \f[C]XDG_CONFIG_HOME\f[R].
+Note that, in this case, xmonad will use \f[C]XDG_DATA_HOME\f[R] and
+\f[C]XDG_CACHE_HOME\f[R] for its data and cache directory respectively.
 .PP
-You can find many extensions to the core feature set in the xmonad\-
+You can find many extensions to the core feature set in the xmonad-
 contrib package, available through your package manager or from
-xmonad.org (http://xmonad.org).
+xmonad.org (https://xmonad.org).
 .SS Modular Configuration
 .PP
-As of \f[I]xmonad\-0.9\f[], any additional Haskell modules may be placed
-in \f[I]~/.xmonad/lib/\f[] are available in GHC's searchpath.
+As of \f[I]xmonad-0.9\f[R], any additional Haskell modules may be placed
+in \f[I]\[ti]/.xmonad/lib/\f[R] are available in GHC\[cq]s searchpath.
 Hierarchical modules are supported: for example, the file
-\f[I]~/.xmonad/lib/XMonad/Stack/MyAdditions.hs\f[] could contain:
+\f[I]\[ti]/.xmonad/lib/XMonad/Stack/MyAdditions.hs\f[R] could contain:
 .IP
 .nf
 \f[C]
-module\ XMonad.Stack.MyAdditions\ (function1)\ where
-\ \ function1\ =\ error\ "function1:\ Not\ implemented\ yet!"
-\f[]
+module XMonad.Stack.MyAdditions (function1) where
+  function1 = error \[dq]function1: Not implemented yet!\[dq]
+\f[R]
 .fi
 .PP
 Your xmonad.hs may then import XMonad.Stack.MyAdditions as if that
-module was contained within xmonad or xmonad\-contrib.
+module was contained within xmonad or xmonad-contrib.
 .SH Bugs
 .PP
 Probably.

man/xmonad.1.html

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-  <meta name="dcterms.date" content="2018-08-20" />
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   <title>XMONAD(1) Tiling Window Manager</title>
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-  <![endif]-->
 </head>
 <body>
-<header>
+<header id="title-block-header">
 <h1 class="title">XMONAD(1) Tiling Window Manager</h1>
 <p class="author"></p>
-<p class="date">20 August 2018</p>
+<p class="date">27 October 2021</p>
 </header>
-<nav id="TOC">
+<nav id="TOC" role="doc-toc">
 <ul>
 <li><a href="#name">Name</a></li>
 <li><a href="#description">Description</a></li>
-<li><a href="#usage">Usage</a><ul>
+<li><a href="#usage">Usage</a>
+<ul>
 <li><a href="#flags">Flags</a></li>
+<li><a href="#default-keyboard-bindings">Default keyboard bindings</a></li>
 </ul></li>
 <li><a href="#examples">Examples</a></li>
-<li><a href="#customization">Customization</a><ul>
+<li><a href="#customization">Customization</a>
+<ul>
 <li><a href="#modular-configuration">Modular Configuration</a></li>
 </ul></li>
 <li><a href="#bugs">Bugs</a></li>
@@ -114,7 +115,7 @@ code span.wa { color: #60a0b0; font-weight: bold; font-style: italic; } /* Warni
 <p>xmonad has several flags which you may pass to the executable. These flags are:</p>
 <dl>
 <dt>–recompile</dt>
-<dd>Recompiles your configuration in <em>~/.xmonad/xmonad.hs</em>
+<dd>Recompiles your <em>xmonad.hs</em> configuration
 </dd>
 <dt>–restart</dt>
 <dd>Causes the currently running <em>xmonad</em> process to restart
@@ -129,7 +130,7 @@ code span.wa { color: #60a0b0; font-weight: bold; font-style: italic; } /* Warni
 <dd>Display detailed version of <em>xmonad</em>
 </dd>
 </dl>
-<p>##Default keyboard bindings</p>
+<h2 id="default-keyboard-bindings">Default keyboard bindings</h2>
 <dl>
 <dt>mod-shift-return</dt>
 <dd>Launch terminal
@@ -231,12 +232,17 @@ code span.wa { color: #60a0b0; font-weight: bold; font-style: italic; } /* Warni
 <p>exec xmonad</p>
 </blockquote>
 <h1 id="customization">Customization</h1>
-<p>xmonad is customized in ~/.xmonad/xmonad.hs, and then restarted with mod-q.</p>
-<p>You can find many extensions to the core feature set in the xmonad- contrib package, available through your package manager or from <a href="http://xmonad.org">xmonad.org</a>.</p>
+<p>xmonad is customized in your <em>xmonad.hs</em>, and then restarted with mod-q. You can choose where your configuration file lives by</p>
+<ol type="1">
+<li>Setting <code>XMONAD_DATA_DIR,</code> <code>XMONAD_CONFIG_DIR</code>, and <code>XMONAD_CACHE_DIR</code>; <em>xmonad.hs</em> is then expected to be in <code>XMONAD_CONFIG_DIR</code>.</li>
+<li>Creating <em>xmonad.hs</em> in <em>~/.xmonad</em>.</li>
+<li>Creating <em>xmonad.hs</em> in <code>XDG_CONFIG_HOME</code>. Note that, in this case, xmonad will use <code>XDG_DATA_HOME</code> and <code>XDG_CACHE_HOME</code> for its data and cache directory respectively.</li>
+</ol>
+<p>You can find many extensions to the core feature set in the xmonad- contrib package, available through your package manager or from <a href="https://xmonad.org">xmonad.org</a>.</p>
 <h2 id="modular-configuration">Modular Configuration</h2>
 <p>As of <em>xmonad-0.9</em>, any additional Haskell modules may be placed in <em>~/.xmonad/lib/</em> are available in GHC’s searchpath. Hierarchical modules are supported: for example, the file <em>~/.xmonad/lib/XMonad/Stack/MyAdditions.hs</em> could contain:</p>
-<div class="sourceCode" id="cb1"><pre class="sourceCode haskell"><code class="sourceCode haskell"><a class="sourceLine" id="cb1-1" data-line-number="1"><span class="kw">module</span> <span class="dt">XMonad.Stack.MyAdditions</span> (function1) <span class="kw">where</span></a>
-<a class="sourceLine" id="cb1-2" data-line-number="2">  function1 <span class="fu">=</span> error <span class="st">&quot;function1: Not implemented yet!&quot;</span></a></code></pre></div>
+<div class="sourceCode" id="cb1"><pre class="sourceCode haskell"><code class="sourceCode haskell"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true"></a><span class="kw">module</span> <span class="dt">XMonad.Stack.MyAdditions</span> (function1) <span class="kw">where</span></span>
+<span id="cb1-2"><a href="#cb1-2" aria-hidden="true"></a>  function1 <span class="ot">=</span> <span class="fu">error</span> <span class="st">&quot;function1: Not implemented yet!&quot;</span></span></code></pre></div>
 <p>Your xmonad.hs may then import XMonad.Stack.MyAdditions as if that module was contained within xmonad or xmonad-contrib.</p>
 <h1 id="bugs">Bugs</h1>
 <p>Probably. If you find any, please report them to the <a href="https://github.com/xmonad/xmonad/issues">bugtracker</a></p>

man/xmonad.1.markdown

@@ -1,6 +1,6 @@
 % XMONAD(1) Tiling Window Manager
 %
-% 20 August 2018
+% 27 October 2021
 
 # Name
 
@@ -58,7 +58,7 @@ xmonad  has  several flags which  you may pass to the executable.
 These flags are:
 
 --recompile
-:   Recompiles your configuration in _~/.xmonad/xmonad.hs_
+:   Recompiles your _xmonad.hs_ configuration
 
 --restart
 :   Causes the currently running _xmonad_ process to restart
@@ -72,9 +72,100 @@ These flags are:
 --verbose-version
 :   Display detailed version of _xmonad_
 
-##Default keyboard bindings
+## Default keyboard bindings
 
-___KEYBINDINGS___
+mod-shift-return
+:     Launch terminal
+
+mod-p
+:     Launch dmenu
+
+mod-shift-p
+:     Launch gmrun
+
+mod-shift-c
+:     Close the focused window
+
+mod-space
+:     Rotate through the available layout algorithms
+
+mod-shift-space
+:     Reset the layouts on the current workspace to default
+
+mod-n
+:     Resize viewed windows to the correct size
+
+mod-tab
+:     Move focus to the next window
+
+mod-shift-tab
+:     Move focus to the previous window
+
+mod-j
+:     Move focus to the next window
+
+mod-k
+:     Move focus to the previous window
+
+mod-m
+:     Move focus to the master window
+
+mod-return
+:     Swap the focused window and the master window
+
+mod-shift-j
+:     Swap the focused window with the next window
+
+mod-shift-k
+:     Swap the focused window with the previous window
+
+mod-h
+:     Shrink the master area
+
+mod-l
+:     Expand the master area
+
+mod-t
+:     Push window back into tiling
+
+mod-comma
+:     Increment the number of windows in the master area
+
+mod-period
+:     Deincrement the number of windows in the master area
+
+mod-shift-q
+:     Quit xmonad
+
+mod-q
+:     Restart xmonad
+
+mod-shift-slash
+:     Run xmessage with a summary of the default keybindings (useful for beginners)
+
+mod-question
+:     Run xmessage with a summary of the default keybindings (useful for beginners)
+
+mod-[1..9]
+:     Switch to workspace N
+
+mod-shift-[1..9]
+:     Move client to workspace N
+
+mod-{w,e,r}
+:     Switch to physical/Xinerama screens 1, 2, or 3
+
+mod-shift-{w,e,r}
+:     Move client to screen 1, 2, or 3
+
+mod-button1
+:     Set the window to floating mode and move by dragging
+
+mod-button2
+:     Raise the window to the top of the stack
+
+mod-button3
+:     Set the window to floating mode and resize by dragging
 
 # Examples
 
@@ -83,8 +174,16 @@ To use xmonad as your window manager add to your _~/.xinitrc_ file:
 > exec xmonad
 
 # Customization
-xmonad is customized in ~/.xmonad/xmonad.hs, and then restarted
-with mod-q.
+xmonad is customized in your _xmonad.hs_, and then restarted with mod-q.
+You can choose where your configuration file lives by
+
+  1. Setting `XMONAD_DATA_DIR,` `XMONAD_CONFIG_DIR`, and
+     `XMONAD_CACHE_DIR`; _xmonad.hs_ is then expected to be in
+     `XMONAD_CONFIG_DIR`.
+  2. Creating _xmonad.hs_ in _~/.xmonad_.
+  3. Creating _xmonad.hs_ in `XDG_CONFIG_HOME`.  Note that, in this
+     case, xmonad will use `XDG_DATA_HOME` and `XDG_CACHE_HOME` for its
+     data and cache directory respectively.
 
 You can find many extensions to the core feature set in the xmonad-
 contrib package, available through your  package  manager  or  from
@@ -107,5 +206,5 @@ module was contained within xmonad or xmonad-contrib.
 # Bugs
 Probably. If you find any, please report them to the [bugtracker]
 
-[xmonad.org]: http://xmonad.org
+[xmonad.org]: https://xmonad.org
 [bugtracker]: https://github.com/xmonad/xmonad/issues

man/xmonad.1.markdown.in

@@ -0,0 +1,119 @@
+% XMONAD(1) Tiling Window Manager
+%
+% 27 October 2021
+
+# Name
+
+xmonad - Tiling Window Manager
+
+# Description
+
+_xmonad_ is a minimalist tiling window manager for X, written in Haskell.
+Windows are managed using automatic layout algorithms, which can be
+dynamically reconfigured. At any time windows are arranged so as to
+maximize the use of screen real estate. All features of the window manager
+are accessible purely from the keyboard: a mouse is entirely optional.
+_xmonad_ is configured in Haskell, and custom layout algorithms may be
+implemented by the user in config files. A principle of _xmonad_ is
+predictability: the user should know in advance precisely the window
+arrangement that will result from any action.
+
+By default, _xmonad_ provides three layout algorithms: tall, wide and
+fullscreen. In tall or wide mode, windows are tiled and arranged to prevent
+overlap and maximize screen use. Sets of windows are grouped together on
+virtual screens, and each screen retains its own layout, which may be
+reconfigured dynamically. Multiple physical monitors are supported via
+Xinerama, allowing simultaneous display of a number of screens.
+
+By utilizing the expressivity of a modern functional language with a rich
+static type system, _xmonad_ provides a complete, featureful window manager
+in less than 1200 lines of code, with an emphasis on correctness and
+robustness. Internal properties of the window manager are checked using a
+combination of static guarantees provided by the type system, and
+type-based automated testing. A benefit of this is that the code is simple
+to understand, and easy to modify.
+
+# Usage
+
+_xmonad_ places each window into a "workspace". Each workspace can have
+any number of windows, which you can cycle though with mod-j and mod-k.
+Windows are either displayed full screen, tiled horizontally, or tiled
+vertically. You can toggle the layout mode with mod-space, which will cycle
+through the available modes.
+
+You can switch to workspace N with mod-N. For example, to switch to
+workspace 5, you would press mod-5. Similarly, you can move the current
+window to another workspace with mod-shift-N.
+
+When running with multiple monitors (Xinerama), each screen has exactly 1
+workspace visible. mod-{w,e,r} switch the focus between screens, while
+shift-mod-{w,e,r} move the current window to that screen. When _xmonad_
+starts, workspace 1 is on screen 1, workspace 2 is on screen 2, etc. When
+switching workspaces to one that is already visible, the current and
+visible workspaces are swapped.
+
+## Flags
+
+xmonad  has  several flags which  you may pass to the executable.
+These flags are:
+
+--recompile
+:   Recompiles your _xmonad.hs_ configuration
+
+--restart
+:   Causes the currently running _xmonad_ process to restart
+
+--replace
+:   Replace the current window manager with xmonad
+
+--version
+:   Display version of _xmonad_
+
+--verbose-version
+:   Display detailed version of _xmonad_
+
+## Default keyboard bindings
+
+___KEYBINDINGS___
+
+# Examples
+
+To use xmonad as your window manager add to your _~/.xinitrc_ file:
+
+> exec xmonad
+
+# Customization
+xmonad is customized in your _xmonad.hs_, and then restarted with mod-q.
+You can choose where your configuration file lives by
+
+  1. Setting `XMONAD_DATA_DIR,` `XMONAD_CONFIG_DIR`, and
+     `XMONAD_CACHE_DIR`; _xmonad.hs_ is then expected to be in
+     `XMONAD_CONFIG_DIR`.
+  2. Creating _xmonad.hs_ in _~/.xmonad_.
+  3. Creating _xmonad.hs_ in `XDG_CONFIG_HOME`.  Note that, in this
+     case, xmonad will use `XDG_DATA_HOME` and `XDG_CACHE_HOME` for its
+     data and cache directory respectively.
+
+You can find many extensions to the core feature set in the xmonad-
+contrib package, available through your  package  manager  or  from
+[xmonad.org].
+
+## Modular Configuration
+As of _xmonad-0.9_, any additional Haskell modules may be placed in
+_~/.xmonad/lib/_ are available in GHC's searchpath. Hierarchical modules
+are supported: for example, the file
+_~/.xmonad/lib/XMonad/Stack/MyAdditions.hs_ could contain:
+
+```haskell
+module XMonad.Stack.MyAdditions (function1) where
+  function1 = error "function1: Not implemented yet!"
+```
+
+Your xmonad.hs may then import XMonad.Stack.MyAdditions as if that
+module was contained within xmonad or xmonad-contrib.
+
+# Bugs
+Probably. If you find any, please report them to the [bugtracker]
+
+[xmonad.org]: https://xmonad.org
+[bugtracker]: https://github.com/xmonad/xmonad/issues

man/xmonad.hs

@@ -123,13 +123,13 @@ myKeys conf@(XConfig {XMonad.modMask = modm}) = M.fromList $
     -- , ((modm              , xK_b     ), sendMessage ToggleStruts)
 
     -- Quit xmonad
-    , ((modm .|. shiftMask, xK_q     ), io (exitWith ExitSuccess))
+    , ((modm .|. shiftMask, xK_q     ), io exitSuccess)
 
     -- Restart xmonad
     , ((modm              , xK_q     ), spawn "xmonad --recompile; xmonad --restart")
 
     -- Run xmessage with a summary of the default keybindings (useful for beginners)
-    , ((modm .|. shiftMask, xK_slash ), spawn ("echo \"" ++ help ++ "\" | xmessage -file -"))
+    , ((modm .|. shiftMask, xK_slash ), xmessage help)
     ]
     ++
 
@@ -154,18 +154,18 @@ myKeys conf@(XConfig {XMonad.modMask = modm}) = M.fromList $
 ------------------------------------------------------------------------
 -- Mouse bindings: default actions bound to mouse events
 --
-myMouseBindings (XConfig {XMonad.modMask = modm}) = M.fromList $
+myMouseBindings (XConfig {XMonad.modMask = modm}) = M.fromList
 
     -- mod-button1, Set the window to floating mode and move by dragging
-    [ ((modm, button1), (\w -> focus w >> mouseMoveWindow w
-                                       >> windows W.shiftMaster))
+    [ ((modm, button1), \w -> focus w >> mouseMoveWindow w
+                                      >> windows W.shiftMaster)
 
     -- mod-button2, Raise the window to the top of the stack
-    , ((modm, button2), (\w -> focus w >> windows W.shiftMaster))
+    , ((modm, button2), \w -> focus w >> windows W.shiftMaster)
 
     -- mod-button3, Set the window to floating mode and resize by dragging
-    , ((modm, button3), (\w -> focus w >> mouseResizeWindow w
-                                       >> windows W.shiftMaster))
+    , ((modm, button3), \w -> focus w >> mouseResizeWindow w
+                                      >> windows W.shiftMaster)
 
     -- you may also bind events to the mouse scroll wheel (button4 and button5)
     ]
@@ -293,6 +293,7 @@ help = unlines ["The default modifier key is 'alt'. Default keybindings:",
     "mod-Space        Rotate through the available layout algorithms",
     "mod-Shift-Space  Reset the layouts on the current workSpace to default",
     "mod-n            Resize/refresh viewed windows to the correct size",
+    "mod-Shift-/      Show this help message with the default keybindings",
     "",
     "-- move focus up or down the window stack",
     "mod-Tab        Move focus to the next window",

src/XMonad/Config.hs

@@ -1,5 +1,6 @@
 {-# OPTIONS_GHC -fno-warn-missing-signatures -fno-warn-orphans #-}
 {-# LANGUAGE TypeFamilies #-}
+{-# LANGUAGE TypeOperators #-}
 -----------------------------------------------------------------------------
 -- |
 -- Module      :  XMonad.Config
@@ -39,7 +40,7 @@ import XMonad.Operations
 import XMonad.ManageHook
 import qualified XMonad.StackSet as W
 import Data.Bits ((.|.))
-import Data.Default
+import Data.Default.Class
 import Data.Monoid
 import qualified Data.Map as M
 import System.Exit
@@ -218,7 +219,7 @@ keys conf@(XConfig {XMonad.modMask = modMask}) = M.fromList $
     , ((modMask              , xK_period), sendMessage (IncMasterN (-1))) -- %! Deincrement the number of windows in the master area
 
     -- quit, or restart
-    , ((modMask .|. shiftMask, xK_q     ), io (exitWith ExitSuccess)) -- %! Quit xmonad
+    , ((modMask .|. shiftMask, xK_q     ), io exitSuccess) -- %! Quit xmonad
     , ((modMask              , xK_q     ), spawn "if type xmonad; then xmonad --recompile && xmonad --restart; else xmessage xmonad not in \\$PATH: \"$PATH\"; fi") -- %! Restart xmonad
 
     , ((modMask .|. shiftMask, xK_slash ), helpCommand) -- %! Run xmessage with a summary of the default keybindings (useful for beginners)
@@ -239,7 +240,7 @@ keys conf@(XConfig {XMonad.modMask = modMask}) = M.fromList $
         , (f, m) <- [(W.view, 0), (W.shift, shiftMask)]]
   where
     helpCommand :: X ()
-    helpCommand = spawn ("echo " ++ show help ++ " | xmessage -file -")
+    helpCommand = xmessage help
 
 -- | Mouse bindings: default actions bound to mouse events
 mouseBindings :: XConfig Layout -> M.Map (KeyMask, Button) (Window -> X ())
@@ -277,6 +278,7 @@ instance (a ~ Choose Tall (Choose (Mirror Tall) Full)) => Default (XConfig a) wh
     , XMonad.handleExtraArgs = \ xs theConf -> case xs of
                 [] -> return theConf
                 _ -> fail ("unrecognized flags:" ++ show xs)
+    , XMonad.extensibleConf     = M.empty
     }
 
 -- | The default set of configuration values itself
@@ -296,6 +298,7 @@ help = unlines ["The default modifier key is 'alt'. Default keybindings:",
     "mod-Space        Rotate through the available layout algorithms",
     "mod-Shift-Space  Reset the layouts on the current workSpace to default",
     "mod-n            Resize/refresh viewed windows to the correct size",
+    "mod-Shift-/      Show this help message with the default keybindings",
     "",
     "-- move focus up or down the window stack",
     "mod-Tab        Move focus to the next window",

src/XMonad/Core.hs

@@ -1,5 +1,13 @@
-{-# LANGUAGE ExistentialQuantification, FlexibleInstances, GeneralizedNewtypeDeriving,
-             MultiParamTypeClasses, TypeSynonymInstances, DeriveDataTypeable #-}
+{-# LANGUAGE CPP #-}
+{-# LANGUAGE DeriveTraversable #-}
+{-# LANGUAGE ExistentialQuantification #-}
+{-# LANGUAGE FlexibleInstances #-}
+{-# LANGUAGE GeneralizedNewtypeDeriving #-}
+{-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE MultiParamTypeClasses #-}
+{-# LANGUAGE NamedFieldPuns #-}
+{-# LANGUAGE ScopedTypeVariables #-}
+{-# LANGUAGE DerivingVia #-}
 
 -----------------------------------------------------------------------------
 -- |
@@ -22,26 +30,32 @@ module XMonad.Core (
     XConf(..), XConfig(..), LayoutClass(..),
     Layout(..), readsLayout, Typeable, Message,
     SomeMessage(..), fromMessage, LayoutMessages(..),
-    StateExtension(..), ExtensionClass(..),
+    StateExtension(..), ExtensionClass(..), ConfExtension(..),
     runX, catchX, userCode, userCodeDef, io, catchIO, installSignalHandlers, uninstallSignalHandlers,
     withDisplay, withWindowSet, isRoot, runOnWorkspaces,
-    getAtom, spawn, spawnPID, xfork, recompile, trace, whenJust, whenX,
-    getXMonadDir, getXMonadCacheDir, getXMonadDataDir, stateFileName,
+    getAtom, spawn, spawnPID, xfork, xmessage, recompile, trace, whenJust, whenX, ifM,
+    getXMonadDir, getXMonadCacheDir, getXMonadDataDir, stateFileName, binFileName,
     atom_WM_STATE, atom_WM_PROTOCOLS, atom_WM_DELETE_WINDOW, atom_WM_TAKE_FOCUS, withWindowAttributes,
-    ManageHook, Query(..), runQuery
+    ManageHook, Query(..), runQuery, Directories'(..), Directories, getDirectories,
   ) where
 
 import XMonad.StackSet hiding (modify)
 
 import Prelude
-import Control.Exception.Extensible (fromException, try, bracket, throw, finally, SomeException(..))
-import qualified Control.Exception.Extensible as E
-import Control.Applicative(Applicative, pure, (<$>), (<*>))
+import Control.Exception (fromException, try, bracket_, throw, finally, SomeException(..))
+import qualified Control.Exception as E
+import Control.Applicative ((<|>), empty)
 import Control.Monad.Fail
+import Control.Monad.Fix (fix)
 import Control.Monad.State
 import Control.Monad.Reader
+import Control.Monad (filterM, guard, void, when)
 import Data.Semigroup
-import Data.Default
+import Data.Traversable (for)
+import Data.Time.Clock (UTCTime)
+import Data.Default.Class
+import System.Environment (lookupEnv)
+import Data.List (isInfixOf, intercalate, (\\))
 import System.FilePath
 import System.IO
 import System.Info
@@ -56,10 +70,8 @@ import System.Exit
 import Graphics.X11.Xlib
 import Graphics.X11.Xlib.Extras (getWindowAttributes, WindowAttributes, Event)
 import Data.Typeable
-import Data.List ((\\))
 import Data.Maybe (isJust,fromMaybe)
-import Data.Monoid hiding ((<>))
-import System.Environment (lookupEnv)
+import Data.Monoid (Ap(..))
 
 import qualified Data.Map as M
 import qualified Data.Set as S
@@ -93,8 +105,8 @@ data XConf = XConf
     , mousePosition :: !(Maybe (Position, Position))
                                       -- ^ position of the mouse according to
                                       -- the event currently being processed
-    , currentEvent :: !(Maybe Event)
-                                      -- ^ event currently being processed
+    , currentEvent :: !(Maybe Event)  -- ^ event currently being processed
+    , directories  :: !Directories    -- ^ directories to use
     }
 
 -- todo, better name
@@ -122,6 +134,11 @@ data XConfig l = XConfig
     , rootMask           :: !EventMask           -- ^ The root events that xmonad is interested in
     , handleExtraArgs    :: !([String] -> XConfig Layout -> IO (XConfig Layout))
                                                  -- ^ Modify the configuration, complain about extra arguments etc. with arguments that are not handled by default
+    , extensibleConf     :: !(M.Map TypeRep ConfExtension)
+                                                 -- ^ Stores custom config information.
+                                                 --
+                                                 -- The module "XMonad.Util.ExtensibleConf" in xmonad-contrib
+                                                 -- provides additional information and a simple interface for using this.
     }
 
 
@@ -135,7 +152,8 @@ type WorkspaceId = String
 newtype ScreenId    = S Int deriving (Eq,Ord,Show,Read,Enum,Num,Integral,Real)
 
 -- | The 'Rectangle' with screen dimensions
-data ScreenDetail   = SD { screenRect :: !Rectangle } deriving (Eq,Show, Read)
+newtype ScreenDetail = SD { screenRect :: Rectangle }
+    deriving (Eq,Show, Read)
 
 ------------------------------------------------------------------------
 
@@ -148,18 +166,8 @@ data ScreenDetail   = SD { screenRect :: !Rectangle } deriving (Eq,Show, Read)
 -- instantiated on 'XConf' and 'XState' automatically.
 --
 newtype X a = X (ReaderT XConf (StateT XState IO) a)
-    deriving (Functor, Monad, MonadFail, MonadIO, MonadState XState, MonadReader XConf, Typeable)
-
-instance Applicative X where
-  pure = return
-  (<*>) = ap
-
-instance Semigroup a => Semigroup (X a) where
-    (<>) = liftM2 (<>)
-
-instance (Monoid a) => Monoid (X a) where
-    mempty  = return mempty
-    mappend = liftM2 mappend
+    deriving (Functor, Applicative, Monad, MonadFail, MonadIO, MonadState XState, MonadReader XConf)
+    deriving (Semigroup, Monoid) via Ap X a
 
 instance Default a => Default (X a) where
     def = return def
@@ -167,16 +175,10 @@ instance Default a => Default (X a) where
 type ManageHook = Query (Endo WindowSet)
 newtype Query a = Query (ReaderT Window X a)
     deriving (Functor, Applicative, Monad, MonadReader Window, MonadIO)
+    deriving (Semigroup, Monoid) via Ap Query a
 
 runQuery :: Query a -> Window -> X a
-runQuery (Query m) w = runReaderT m w
-
-instance Semigroup a => Semigroup (Query a) where
-    (<>) = liftM2 (<>)
-
-instance Monoid a => Monoid (Query a) where
-    mempty  = return mempty
-    mappend = liftM2 mappend
+runQuery (Query m) = runReaderT m
 
 instance Default a => Default (Query a) where
     def = return def
@@ -193,7 +195,7 @@ catchX job errcase = do
     st <- get
     c <- ask
     (a, s') <- io $ runX c st job `E.catch` \e -> case fromException e of
-                        Just x -> throw e `const` (x `asTypeOf` ExitSuccess)
+                        Just (_ :: ExitCode) -> throw e
                         _ -> do hPrint stderr e; runX c st errcase
     put s'
     return a
@@ -201,12 +203,12 @@ catchX job errcase = do
 -- | Execute the argument, catching all exceptions.  Either this function or
 -- 'catchX' should be used at all callsites of user customized code.
 userCode :: X a -> X (Maybe a)
-userCode a = catchX (Just `liftM` a) (return Nothing)
+userCode a = catchX (Just <$> a) (return Nothing)
 
 -- | Same as userCode but with a default argument to return instead of using
 -- Maybe, provided for convenience.
 userCodeDef :: a -> X a -> X a
-userCodeDef defValue a = fromMaybe defValue `liftM` userCode a
+userCodeDef defValue a = fromMaybe defValue <$> userCode a
 
 -- ---------------------------------------------------------------------
 -- Convenient wrappers to state
@@ -227,7 +229,7 @@ withWindowAttributes dpy win f = do
 
 -- | True if the given window is the root window
 isRoot :: Window -> X Bool
-isRoot w = (w==) <$> asks theRoot
+isRoot w = asks $ (w ==) . theRoot
 
 -- | Wrapper for the common case of atom internment
 getAtom :: String -> X Atom
@@ -255,14 +257,18 @@ readsLayout (Layout l) s = [(Layout (asTypeOf x l), rs) | (x, rs) <- reads s]
 -- | Every layout must be an instance of 'LayoutClass', which defines
 -- the basic layout operations along with a sensible default for each.
 --
--- Minimal complete definition:
+-- All of the methods have default implementations, so there is no
+-- minimal complete definition.  They do, however, have a dependency
+-- structure by default; this is something to be aware of should you
+-- choose to implement one of these methods.  Here is how a minimal
+-- complete definition would look like if we did not provide any default
+-- implementations:
 --
--- * 'runLayout' || (('doLayout' || 'pureLayout') && 'emptyLayout'), and
+-- * 'runLayout' || (('doLayout' || 'pureLayout') && 'emptyLayout')
 --
 -- * 'handleMessage' || 'pureMessage'
 --
--- You should also strongly consider implementing 'description',
--- although it is not required.
+-- * 'description'
 --
 -- Note that any code which /uses/ 'LayoutClass' methods should only
 -- ever call 'runLayout', 'handleMessage', and 'description'!  In
@@ -271,7 +277,7 @@ readsLayout (Layout l) s = [(Layout (asTypeOf x l), rs) | (x, rs) <- reads s]
 -- 'runLayout', 'handleMessage', and so on.  This ensures that the
 -- proper methods will be used, regardless of the particular methods
 -- that any 'LayoutClass' instance chooses to define.
-class Show (layout a) => LayoutClass layout a where
+class (Show (layout a), Typeable layout) => LayoutClass layout a where
 
     -- | By default, 'runLayout' calls 'doLayout' if there are any
     --   windows to be laid out, and 'emptyLayout' otherwise.  Most
@@ -373,12 +379,12 @@ instance Message Event
 -- layouts) should consider handling.
 data LayoutMessages = Hide              -- ^ sent when a layout becomes non-visible
                     | ReleaseResources  -- ^ sent when xmonad is exiting or restarting
-    deriving (Typeable, Eq)
+    deriving Eq
 
 instance Message LayoutMessages
 
 -- ---------------------------------------------------------------------
--- Extensible state
+-- Extensible state/config
 --
 
 -- | Every module must make the data it wants to store
@@ -386,6 +392,7 @@ instance Message LayoutMessages
 --
 -- Minimal complete definition: initialValue
 class Typeable a => ExtensionClass a where
+    {-# MINIMAL initialValue #-}
     -- | Defines an initial value for the state extension
     initialValue :: a
     -- | Specifies whether the state extension should be
@@ -404,10 +411,17 @@ data StateExtension =
   | forall a. (Read a, Show a, ExtensionClass a) => PersistentExtension a
     -- ^ Persistent extension
 
+-- | Existential type to store a config extension.
+data ConfExtension = forall a. Typeable a => ConfExtension a
+
 -- ---------------------------------------------------------------------
--- | General utilities
---
--- Lift an 'IO' action into the 'X' monad
+-- General utilities
+
+-- | If-then-else lifted to a 'Monad'.
+ifM :: Monad m => m Bool -> m a -> m a -> m a
+ifM mb t f = mb >>= \b -> if b then t else f
+
+-- | Lift an 'IO' action into the 'X' monad
 io :: MonadIO m => IO a -> m a
 io = liftIO
 
@@ -421,7 +435,7 @@ catchIO f = io (f `E.catch` \(SomeException e) -> hPrint stderr e >> hFlush stde
 --
 -- Note this function assumes your locale uses utf8.
 spawn :: MonadIO m => String -> m ()
-spawn x = spawnPID x >> return ()
+spawn x = void $ spawnPID x
 
 -- | Like 'spawn', but returns the 'ProcessID' of the launched application
 spawnPID :: MonadIO m => String -> m ProcessID
@@ -435,10 +449,25 @@ xfork x = io . forkProcess . finally nullStdin $ do
                 x
  where
     nullStdin = do
+#if MIN_VERSION_unix(2,8,0)
+        fd <- openFd "/dev/null" ReadOnly defaultFileFlags
+#else
         fd <- openFd "/dev/null" ReadOnly Nothing defaultFileFlags
+#endif
         dupTo fd stdInput
         closeFd fd
 
+-- | Use @xmessage@ to show information to the user.
+xmessage :: MonadIO m => String -> m ()
+xmessage msg = void . xfork $ do
+    xmessageBin <- fromMaybe "xmessage" <$> liftIO (lookupEnv "XMONAD_XMESSAGE")
+    executeFile xmessageBin True
+        [ "-default", "okay"
+        , "-xrm", "*international:true"
+        , "-xrm", "*fontSet:-*-fixed-medium-r-normal-*-18-*-*-*-*-*-*-*,-*-fixed-*-*-*-*-18-*-*-*-*-*-*-*,-*-*-*-*-*-*-18-*-*-*-*-*-*-*"
+        , msg
+        ] Nothing
+
 -- | This is basically a map function, running a function in the 'X' monad on
 -- each workspace with the output of that function being the modified workspace.
 runOnWorkspaces :: (WindowSpace -> X WindowSpace) -> X ()
@@ -449,137 +478,302 @@ runOnWorkspaces job = do
              $ current ws : visible ws
     modify $ \s -> s { windowset = ws { current = c, visible = v, hidden = h } }
 
--- | Return the path to the xmonad configuration directory.  This
--- directory is where user configuration files are stored (e.g, the
--- xmonad.hs file).  You may also create a @lib@ subdirectory in the
--- configuration directory and the default recompile command will add
--- it to the GHC include path.
+-- | All the directories that xmonad will use.  They will be used for
+-- the following purposes:
 --
--- Several directories are considered.  In order of
--- preference:
+-- * @dataDir@: This directory is used by XMonad to store data files
+-- such as the run-time state file.
 --
---   1. The directory specified in the @XMONAD_CONFIG_DIR@ environment variable.
---   2. The @~\/.xmonad@ directory.
---   3. The @XDG_CONFIG_HOME/xmonad@ directory.
+-- * @cfgDir@: This directory is where user configuration files are
+-- stored (e.g, the xmonad.hs file).  You may also create a @lib@
+-- subdirectory in the configuration directory and the default recompile
+-- command will add it to the GHC include path.
 --
--- The first directory that exists will be used.  If none of the
--- directories exist then (1) will be used if it is set, otherwise (2)
--- will be used.  Either way, a directory will be created if necessary.
-getXMonadDir :: MonadIO m => m String
-getXMonadDir =
-    findFirstDirWithEnv "XMONAD_CONFIG_DIR"
-      [ getAppUserDataDirectory "xmonad"
-      , getXDGDirectory XDGConfig "xmonad"
-      ]
+-- * @cacheDir@: This directory is used to store temporary files that
+-- can easily be recreated such as the configuration binary and any
+-- intermediate object files generated by GHC.
+-- Also, the XPrompt history file goes here.
+--
+-- For how these directories are chosen, see 'getDirectories'.
+--
+data Directories' a = Directories
+    { dataDir  :: !a
+    , cfgDir   :: !a
+    , cacheDir :: !a
+    }
+    deriving (Show, Functor, Foldable, Traversable)
 
--- | Return the path to the xmonad cache directory.  This directory is
--- used to store temporary files that can easily be recreated.  For
--- example, the XPrompt history file.
---
--- Several directories are considered.  In order of preference:
---
---   1. The directory specified in the @XMONAD_CACHE_DIR@ environment variable.
---   2. The @~\/.xmonad@ directory.
---   3. The @XDG_CACHE_HOME/xmonad@ directory.
---
--- The first directory that exists will be used.  If none of the
--- directories exist then (1) will be used if it is set, otherwise (2)
--- will be used.  Either way, a directory will be created if necessary.
-getXMonadCacheDir :: MonadIO m => m String
-getXMonadCacheDir =
-    findFirstDirWithEnv "XMONAD_CACHE_DIR"
-      [ getAppUserDataDirectory "xmonad"
-      , getXDGDirectory XDGCache "xmonad"
-      ]
+-- | Convenient type alias for the most common case in which one might
+-- want to use the 'Directories' type.
+type Directories = Directories' FilePath
 
--- | Return the path to the xmonad data directory.  This directory is
--- used by XMonad to store data files such as the run-time state file
--- and the configuration binary generated by GHC.
+-- | Build up the 'Dirs' that xmonad will use.  They are chosen as
+-- follows:
 --
--- Several directories are considered.  In order of preference:
+-- 1. If all three of xmonad's environment variables (@XMONAD_DATA_DIR@,
+--    @XMONAD_CONFIG_DIR@, and @XMONAD_CACHE_DIR@) are set, use them.
+-- 2. If there is a build script called @build@ or configuration
+--    @xmonad.hs@ in @~\/.xmonad@, set all three directories to
+--    @~\/.xmonad@.
+-- 3. Otherwise, use the @xmonad@ directory in @XDG_DATA_HOME@,
+--    @XDG_CONFIG_HOME@, and @XDG_CACHE_HOME@ (or their respective
+--    fallbacks).  These directories are created if necessary.
 --
---   1. The directory specified in the @XMONAD_DATA_DIR@ environment variable.
---   2. The @~\/.xmonad@ directory.
---   3. The @XDG_DATA_HOME/xmonad@ directory.
+-- The xmonad configuration file (or the build script, if present) is
+-- always assumed to be in @cfgDir@.
 --
--- The first directory that exists will be used.  If none of the
--- directories exist then (1) will be used if it is set, otherwise (2)
--- will be used.  Either way, a directory will be created if necessary.
-getXMonadDataDir :: MonadIO m => m String
-getXMonadDataDir =
-    findFirstDirWithEnv "XMONAD_DATA_DIR"
-      [ getAppUserDataDirectory "xmonad"
-      , getXDGDirectory XDGData "xmonad"
-      ]
-
--- | Helper function that will find the first existing directory and
--- return its path.  If none of the directories can be found, create
--- and return the first from the list.  If the list is empty this
--- function returns the historical @~\/.xmonad@ directory.
-findFirstDirOf :: MonadIO m => [IO FilePath] -> m FilePath
-findFirstDirOf []        = findFirstDirOf [getAppUserDataDirectory "xmonad"]
-findFirstDirOf possibles = do
-    found <- go possibles
-
-    case found of
-      Just path -> return path
-      Nothing   -> do
-        primary <- io (head possibles)
-        io (createDirectoryIfMissing True primary)
-        return primary
-
+getDirectories :: IO Directories
+getDirectories = xmEnvDirs <|> xmDirs <|> xdgDirs
   where
-    go []     = return Nothing
-    go (x:xs) = do
-      dir    <- io x
-      exists <- io (doesDirectoryExist dir)
-      if exists then return (Just dir) else go xs
+    -- | Check for xmonad's environment variables first
+    xmEnvDirs :: IO Directories
+    xmEnvDirs = do
+        let xmEnvs = Directories{ dataDir  = "XMONAD_DATA_DIR"
+                                , cfgDir   = "XMONAD_CONFIG_DIR"
+                                , cacheDir = "XMONAD_CACHE_DIR"
+                                }
+        maybe empty pure . sequenceA =<< traverse getEnv xmEnvs
 
--- | Simple wrapper around @findFirstDirOf@ that allows the primary
--- path to be specified by an environment variable.
-findFirstDirWithEnv :: MonadIO m => String -> [IO FilePath] -> m FilePath
-findFirstDirWithEnv envName paths = do
-    envPath' <- io (getEnv envName)
+    -- | Check whether the config file or a build script is in the
+    -- @~\/.xmonad@ directory
+    xmDirs :: IO Directories
+    xmDirs = do
+        xmDir <- getAppUserDataDirectory "xmonad"
+        conf  <- doesFileExist $ xmDir </> "xmonad.hs"
+        build <- doesFileExist $ xmDir </> "build"
 
-    case envPath' of
-      Nothing      -> findFirstDirOf paths
-      Just envPath -> findFirstDirOf (return envPath:paths)
+        -- Place *everything* in ~/.xmonad if yes
+        guard $ conf || build
+        pure Directories{ dataDir = xmDir, cfgDir = xmDir, cacheDir = xmDir }
 
--- | Helper function to retrieve the various XDG directories.
--- This has been based on the implementation shipped with GHC version 8.0.1 or
--- higher. Put here to preserve compatibility with older GHC versions.
-getXDGDirectory :: XDGDirectory -> FilePath -> IO FilePath
-getXDGDirectory xdgDir suffix =
-  normalise . (</> suffix) <$>
-  case xdgDir of
-    XDGData   -> get "XDG_DATA_HOME"   ".local/share"
-    XDGConfig -> get "XDG_CONFIG_HOME" ".config"
-    XDGCache  -> get "XDG_CACHE_HOME"  ".cache"
+    -- | Use XDG directories as a fallback
+    xdgDirs :: IO Directories
+    xdgDirs =
+        for Directories{ dataDir = XdgData, cfgDir = XdgConfig, cacheDir = XdgCache }
+            $ \dir -> do d <- getXdgDirectory dir "xmonad"
+                         d <$ createDirectoryIfMissing True d
+
+-- | Return the path to the xmonad configuration directory.
+getXMonadDir :: X String
+getXMonadDir = asks (cfgDir . directories)
+{-# DEPRECATED getXMonadDir "Use `asks (cfgDir . directories)' instead." #-}
+
+-- | Return the path to the xmonad cache directory.
+getXMonadCacheDir :: X String
+getXMonadCacheDir = asks (cacheDir . directories)
+{-# DEPRECATED getXMonadCacheDir "Use `asks (cacheDir . directories)' instead." #-}
+
+-- | Return the path to the xmonad data directory.
+getXMonadDataDir :: X String
+getXMonadDataDir = asks (dataDir . directories)
+{-# DEPRECATED getXMonadDataDir "Use `asks (dataDir . directories)' instead." #-}
+
+binFileName, buildDirName :: Directories -> FilePath
+binFileName  Directories{ cacheDir } = cacheDir </> "xmonad-" <> arch <> "-" <> os
+buildDirName Directories{ cacheDir } = cacheDir </> "build-" <> arch <> "-" <> os
+
+errFileName, stateFileName :: Directories -> FilePath
+errFileName   Directories{ dataDir } = dataDir </> "xmonad.errors"
+stateFileName Directories{ dataDir } = dataDir </> "xmonad.state"
+
+srcFileName, libFileName :: Directories -> FilePath
+srcFileName Directories{ cfgDir } = cfgDir </> "xmonad.hs"
+libFileName Directories{ cfgDir } = cfgDir </> "lib"
+
+buildScriptFileName, stackYamlFileName, nixFlakeFileName, nixDefaultFileName :: Directories -> FilePath
+buildScriptFileName Directories{ cfgDir } = cfgDir </> "build"
+stackYamlFileName   Directories{ cfgDir } = cfgDir </> "stack.yaml"
+nixFlakeFileName    Directories{ cfgDir } = cfgDir </> "flake.nix"
+nixDefaultFileName  Directories{ cfgDir } = cfgDir </> "default.nix"
+
+-- | Compilation method for xmonad configuration.
+data Compile
+  = CompileGhc
+  | CompileStackGhc FilePath
+  | CompileNixFlake
+  | CompileNixDefault
+  | CompileScript FilePath
+    deriving (Show)
+
+-- | Detect compilation method by looking for known file names in xmonad
+-- configuration directory.
+detectCompile :: Directories -> IO Compile
+detectCompile dirs =
+  tryScript <|> tryStack <|> tryNixFlake <|> tryNixDefault <|> useGhc
   where
-    get name fallback = do
-      env <- lookupEnv name
-      case env of
-        Nothing -> fallback'
-        Just path
-          | isRelative path -> fallback'
-          | otherwise -> return path
-      where
-        fallback' = (</> fallback) <$> getHomeDirectory
-data XDGDirectory = XDGData | XDGConfig | XDGCache
+    buildScript = buildScriptFileName dirs
+    stackYaml = stackYamlFileName dirs
+    flakeNix = nixFlakeFileName dirs
+    defaultNix = nixDefaultFileName dirs
 
--- | Get the name of the file used to store the xmonad window state.
-stateFileName :: (Functor m, MonadIO m) => m FilePath
-stateFileName = (</> "xmonad.state") <$> getXMonadDataDir
+    tryScript = do
+        guard =<< doesFileExist buildScript
+        isExe <- isExecutable buildScript
+        if isExe
+          then do
+            trace $ "XMonad will use build script at " <> show buildScript <> " to recompile."
+            pure $ CompileScript buildScript
+          else do
+            trace $ "XMonad will not use build script, because " <> show buildScript <> " is not executable."
+            trace $ "Suggested resolution to use it: chmod u+x " <> show buildScript
+            empty
 
--- | 'recompile force', recompile the xmonad configuration file when
--- any of the following apply:
+    tryNixFlake = do
+      guard =<< doesFileExist flakeNix
+      canonNixFlake <- canonicalizePath flakeNix
+      trace $ "XMonad will use nix flake at " <> show canonNixFlake <> " to recompile"
+      pure CompileNixFlake
+
+    tryNixDefault = do
+      guard =<< doesFileExist defaultNix
+      canonNixDefault <- canonicalizePath defaultNix
+      trace $ "XMonad will use nix file at " <> show canonNixDefault <> " to recompile"
+      pure CompileNixDefault
+
+    tryStack = do
+        guard =<< doesFileExist stackYaml
+        canonStackYaml <- canonicalizePath stackYaml
+        trace $ "XMonad will use stack ghc --stack-yaml " <> show canonStackYaml <> " to recompile."
+        pure $ CompileStackGhc canonStackYaml
+
+    useGhc = do
+        trace $ "XMonad will use ghc to recompile, because none of "
+                <> intercalate ", "
+                     [ show buildScript
+                     , show stackYaml
+                     , show flakeNix
+                     , show defaultNix
+                     ] <> " exist."
+        pure CompileGhc
+
+-- | Determine whether or not the file found at the provided filepath is executable.
+isExecutable :: FilePath -> IO Bool
+isExecutable f = E.catch (executable <$> getPermissions f) (\(SomeException _) -> return False)
+
+-- | Should we recompile xmonad configuration? Is it newer than the compiled
+-- binary?
+shouldCompile :: Directories -> Compile -> IO Bool
+shouldCompile dirs CompileGhc = do
+    libTs <- mapM getModTime . Prelude.filter isSource =<< allFiles (libFileName dirs)
+    srcT <- getModTime (srcFileName dirs)
+    binT <- getModTime (binFileName dirs)
+    if any (binT <) (srcT : libTs)
+        then True <$ trace "XMonad recompiling because some files have changed."
+        else False <$ trace "XMonad skipping recompile because it is not forced (e.g. via --recompile), and neither xmonad.hs nor any *.hs / *.lhs / *.hsc files in lib/ have been changed."
+  where
+    isSource = flip elem [".hs",".lhs",".hsc"] . takeExtension
+    allFiles t = do
+        let prep = map (t</>) . Prelude.filter (`notElem` [".",".."])
+        cs <- prep <$> E.catch (getDirectoryContents t) (\(SomeException _) -> return [])
+        ds <- filterM doesDirectoryExist cs
+        concat . ((cs \\ ds):) <$> mapM allFiles ds
+shouldCompile dirs CompileStackGhc{} = do
+    stackYamlT <- getModTime (stackYamlFileName dirs)
+    binT <- getModTime (binFileName dirs)
+    if binT < stackYamlT
+        then True <$ trace "XMonad recompiling because some files have changed."
+        else shouldCompile dirs CompileGhc
+shouldCompile _dirs CompileNixFlake{} = True <$ trace "XMonad recompiling because flake recompilation is being used."
+shouldCompile _dirs CompileNixDefault{} = True <$ trace "XMonad recompiling because nix recompilation is being used."
+shouldCompile _dirs CompileScript{} =
+    True <$ trace "XMonad recompiling because a custom build script is being used."
+
+getModTime :: FilePath -> IO (Maybe UTCTime)
+getModTime f = E.catch (Just <$> getModificationTime f) (\(SomeException _) -> return Nothing)
+
+-- | Compile the configuration.
+compile :: Directories -> Compile -> IO ExitCode
+compile dirs method =
+    bracket_ uninstallSignalHandlers installSignalHandlers $
+        withFile (errFileName dirs) WriteMode $ \err -> do
+            let run = runProc (cfgDir dirs) err
+            case method of
+                CompileGhc -> do
+                    ghc <- fromMaybe "ghc" <$> lookupEnv "XMONAD_GHC"
+                    run ghc ghcArgs
+                CompileStackGhc stackYaml ->
+                    run "stack" ["build", "--silent", "--stack-yaml", stackYaml] .&&.
+                    run "stack" ("ghc" : "--stack-yaml" : stackYaml : "--" : ghcArgs)
+                CompileNixFlake ->
+                    run "nix" ["build"] >>= andCopyFromResultDir
+                CompileNixDefault ->
+                    run "nix-build" [] >>= andCopyFromResultDir
+                CompileScript script ->
+                    run script [binFileName dirs]
+  where
+    ghcArgs = [ "--make"
+              , "xmonad.hs"
+              , "-i" -- only look in @lib@
+              , "-ilib"
+              , "-fforce-recomp"
+              , "-main-is", "main"
+              , "-v0"
+              , "-outputdir", buildDirName dirs
+              , "-o", binFileName dirs
+              ]
+    andCopyFromResultDir exitCode = do
+      if exitCode == ExitSuccess then copyFromResultDir else return exitCode
+    findM p = foldr (\x -> ifM (p x) (pure $ Just x)) (pure Nothing)
+    catchAny :: IO a -> (SomeException -> IO a) -> IO a
+    catchAny = E.catch
+    copyFromResultDir = do
+      let binaryDirectory = cfgDir dirs </> "result" </> "bin"
+      binFiles <- map (binaryDirectory </>) <$> catchAny (listDirectory binaryDirectory) (\_ -> return [])
+      mfilepath <- findM isExecutable binFiles
+      case mfilepath of
+        Just filepath -> copyFile filepath (binFileName dirs) >> return ExitSuccess
+        Nothing -> return $ ExitFailure 1
+
+    -- waitForProcess =<< System.Process.runProcess, but without closing the err handle
+    runProc cwd err exe args = do
+        hPutStrLn err $ unwords $ "$" : exe : args
+        hFlush err
+        (_, _, _, h) <- createProcess_ "runProc" (proc exe args){ cwd = Just cwd, std_err = UseHandle err }
+        waitForProcess h
+
+    cmd1 .&&. cmd2 = cmd1 >>= \case
+        ExitSuccess -> cmd2
+        e -> pure e
+
+-- | Check GHC output for deprecation warnings and notify the user if there
+-- were any. Report success otherwise.
+checkCompileWarnings :: Directories -> IO ()
+checkCompileWarnings dirs = do
+    ghcErr <- readFile (errFileName dirs)
+    if "-Wdeprecations" `isInfixOf` ghcErr
+      then do
+        let msg = unlines $
+                ["Deprecations detected while compiling xmonad config: " <> srcFileName dirs]
+                ++ lines ghcErr
+                ++ ["","Please correct them or silence using {-# OPTIONS_GHC -Wno-deprecations #-}."]
+        trace msg
+        xmessage msg
+      else
+        trace "XMonad recompilation process exited with success!"
+
+-- | Notify the user that compilation failed and what was wrong.
+compileFailed :: Directories -> ExitCode -> IO ()
+compileFailed dirs status = do
+    ghcErr <- readFile (errFileName dirs)
+    let msg = unlines $
+            ["Errors detected while compiling xmonad config: " <> srcFileName dirs]
+            ++ lines (if null ghcErr then show status else ghcErr)
+            ++ ["","Please check the file for errors."]
+    -- nb, the ordering of printing, then forking, is crucial due to
+    -- lazy evaluation
+    trace msg
+    xmessage msg
+
+-- | Recompile the xmonad configuration file when any of the following apply:
 --
---      * force is 'True'
+--  * force is 'True'
 --
---      * the xmonad executable does not exist
+--  * the xmonad executable does not exist
 --
---      * the xmonad executable is older than xmonad.hs or any file in
---        the @lib@ directory (under the configuration directory).
+--  * the xmonad executable is older than @xmonad.hs@ or any file in
+--    the @lib@ directory (under the configuration directory)
+--
+--  * custom @build@ script is being used
 --
 -- The -i flag is used to restrict recompilation to the xmonad.hs file only,
 -- and any files in the aforementioned @lib@ directory.
@@ -590,106 +784,21 @@ stateFileName = (</> "xmonad.state") <$> getXMonadDataDir
 --
 -- 'False' is returned if there are compilation errors.
 --
-recompile :: MonadIO m => Bool -> m Bool
-recompile force = io $ do
-    cfgdir  <- getXMonadDir
-    datadir <- getXMonadDataDir
-    let binn = "xmonad-"++arch++"-"++os
-        bin  = datadir </> binn
-        err  = datadir </> "xmonad.errors"
-        src  = cfgdir </> "xmonad.hs"
-        lib  = cfgdir </> "lib"
-        buildscript = cfgdir </> "build"
-
-    libTs <- mapM getModTime . Prelude.filter isSource =<< allFiles lib
-    srcT <- getModTime src
-    binT <- getModTime bin
-
-    useBuildscript <- do
-      exists <- doesFileExist buildscript
-      if exists
-        then do
-          isExe <- isExecutable buildscript
-          if isExe
-            then do
-              trace $ "XMonad will use build script at " ++ show buildscript ++ " to recompile."
-              return True
-            else do
-              trace $ unlines
-                [ "XMonad will not use build script, because " ++ show buildscript ++ " is not executable."
-                , "Suggested resolution to use it: chmod u+x " ++ show buildscript
-                ]
-              return False
-        else do
-          trace $
-            "XMonad will use ghc to recompile, because " ++ show buildscript ++ " does not exist."
-          return False
-
-    shouldRecompile <-
-      if useBuildscript || force
-        then return True
-        else if any (binT <) (srcT : libTs)
-          then do
-            trace "XMonad doing recompile because some files have changed."
-            return True
-          else do
-            trace "XMonad skipping recompile because it is not forced (e.g. via --recompile), and neither xmonad.hs nor any *.hs / *.lhs / *.hsc files in lib/ have been changed."
-            return False
-
-    if shouldRecompile
+recompile :: MonadIO m => Directories -> Bool -> m Bool
+recompile dirs force = io $ do
+    method <- detectCompile dirs
+    willCompile <- if force
+        then True <$ trace "XMonad recompiling (forced)."
+        else shouldCompile dirs method
+    if willCompile
       then do
-        -- temporarily disable SIGCHLD ignoring:
-        uninstallSignalHandlers
-        status <- bracket (openFile err WriteMode) hClose $ \errHandle ->
-            waitForProcess =<< if useBuildscript
-                               then compileScript bin cfgdir buildscript errHandle
-                               else compileGHC bin cfgdir errHandle
-
-        -- re-enable SIGCHLD:
-        installSignalHandlers
-
-        -- now, if it fails, run xmessage to let the user know:
+        status <- compile dirs method
         if status == ExitSuccess
-            then trace "XMonad recompilation process exited with success!"
-            else do
-                ghcErr <- readFile err
-                let msg = unlines $
-                        ["Error detected while loading xmonad configuration file: " ++ src]
-                        ++ lines (if null ghcErr then show status else ghcErr)
-                        ++ ["","Please check the file for errors."]
-                -- nb, the ordering of printing, then forking, is crucial due to
-                -- lazy evaluation
-                hPutStrLn stderr msg
-                forkProcess $ executeFile "xmessage" True ["-default", "okay", replaceUnicode msg] Nothing
-                return ()
-        return (status == ExitSuccess)
-      else return True
- where getModTime f = E.catch (Just <$> getModificationTime f) (\(SomeException _) -> return Nothing)
-       isSource = flip elem [".hs",".lhs",".hsc"] . takeExtension
-       isExecutable f = E.catch (executable <$> getPermissions f) (\(SomeException _) -> return False)
-       allFiles t = do
-            let prep = map (t</>) . Prelude.filter (`notElem` [".",".."])
-            cs <- prep <$> E.catch (getDirectoryContents t) (\(SomeException _) -> return [])
-            ds <- filterM doesDirectoryExist cs
-            concat . ((cs \\ ds):) <$> mapM allFiles ds
-       -- Replace some of the unicode symbols GHC uses in its output
-       replaceUnicode = map $ \c -> case c of
-           '\8226' -> '*'  -- •
-           '\8216' -> '`'  -- ‘
-           '\8217' -> '`'  -- ’
-           _ -> c
-       compileGHC bin dir errHandle =
-         runProcess "ghc" ["--make"
-                          , "xmonad.hs"
-                          , "-i"
-                          , "-ilib"
-                          , "-fforce-recomp"
-                          , "-main-is", "main"
-                          , "-v0"
-                          , "-o", bin
-                          ] (Just dir) Nothing Nothing Nothing (Just errHandle)
-       compileScript bin dir script errHandle =
-         runProcess script [bin] (Just dir) Nothing Nothing Nothing (Just errHandle)
+            then checkCompileWarnings dirs
+            else compileFailed dirs status
+        pure $ status == ExitSuccess
+      else
+        pure True
 
 -- | Conditionally run an action, using a @Maybe a@ to decide.
 whenJust :: Monad m => Maybe a -> (a -> m ()) -> m ()

src/XMonad/Layout.hs

@@ -1,4 +1,6 @@
-{-# LANGUAGE FlexibleInstances, MultiParamTypeClasses, PatternGuards, TypeSynonymInstances, DeriveDataTypeable #-}
+{-# LANGUAGE FlexibleInstances #-}
+{-# LANGUAGE MultiParamTypeClasses #-}
+{-# LANGUAGE PatternGuards #-}
 
 -- --------------------------------------------------------------------------
 -- |
@@ -8,7 +10,7 @@
 --
 -- Maintainer  :  spencerjanssen@gmail.com
 -- Stability   :  unstable
--- Portability :  not portable, Typeable deriving, mtl, posix
+-- Portability :  not portable, mtl, posix
 --
 -- The collection of core layouts.
 --
@@ -16,7 +18,7 @@
 
 module XMonad.Layout (
     Full(..), Tall(..), Mirror(..),
-    Resize(..), IncMasterN(..), Choose, (|||), ChangeLayout(..),
+    Resize(..), IncMasterN(..), Choose(..), (|||), CLR(..), ChangeLayout(..), JumpToLayout(..),
     mirrorRect, splitVertically,
     splitHorizontally, splitHorizontallyBy, splitVerticallyBy,
 
@@ -27,6 +29,7 @@ module XMonad.Layout (
 import XMonad.Core
 
 import Graphics.X11 (Rectangle(..))
+import Graphics.X11.Xlib.Extras ( Event(DestroyWindowEvent) )
 import qualified XMonad.StackSet as W
 import Control.Arrow ((***), second)
 import Control.Monad
@@ -35,10 +38,10 @@ import Data.Maybe (fromMaybe)
 ------------------------------------------------------------------------
 
 -- | Change the size of the master pane.
-data Resize     = Shrink | Expand   deriving Typeable
+data Resize     = Shrink | Expand
 
 -- | Increase the number of clients in the master pane.
-data IncMasterN = IncMasterN !Int    deriving Typeable
+newtype IncMasterN = IncMasterN Int
 
 instance Message Resize
 instance Message IncMasterN
@@ -59,9 +62,13 @@ data Tall a = Tall { tallNMaster :: !Int               -- ^ The default number o
 
 -- a nice pure layout, lots of properties for the layout, and its messages, in Properties.hs
 instance LayoutClass Tall a where
-    pureLayout (Tall nmaster _ frac) r s = zip ws rs
+    pureLayout (Tall nmaster _ frac) r s
+        | frac == 0 = drop nmaster layout
+        | frac == 1 = take nmaster layout
+        | otherwise = layout
       where ws = W.integrate s
             rs = tile frac r nmaster (length ws)
+            layout = zip ws rs
 
     pureMessage (Tall nmaster delta frac) m =
             msum [fmap resize     (fromMessage m)
@@ -77,7 +84,7 @@ instance LayoutClass Tall a where
 -- algorithm.
 --
 -- The screen is divided into two panes. All clients are
--- then partioned between these two panes. One pane, the master, by
+-- then partitioned between these two panes. One pane, the master, by
 -- convention has the least number of windows in it.
 tile
     :: Rational  -- ^ @frac@, what proportion of the screen to devote to the master area
@@ -131,23 +138,53 @@ mirrorRect (Rectangle rx ry rw rh) = Rectangle ry rx rh rw
 -- LayoutClass selection manager
 -- Layouts that transition between other layouts
 
--- | Messages to change the current layout.
-data ChangeLayout = FirstLayout | NextLayout deriving (Eq, Show, Typeable)
+-- | Messages to change the current layout.  Also see 'JumpToLayout'.
+data ChangeLayout = FirstLayout | NextLayout deriving (Eq, Show)
 
 instance Message ChangeLayout
 
+-- | A message to jump to a particular layout, specified by its
+-- description string.
+--
+-- The argument given to a 'JumpToLayout' message should be the
+-- @description@ of the layout to be selected.  If you use
+-- "XMonad.Hooks.DynamicLog" from @xmonad-contrib@, this is the name of
+-- the layout displayed in your status bar.  Alternatively, you can use
+-- GHCi to determine the proper name to use.  For example:
+--
+-- > $ ghci
+-- > GHCi, version 6.8.2: http://www.haskell.org/ghc/  :? for help
+-- > Loading package base ... linking ... done.
+-- > :set prompt "> "    -- don't show loaded module names
+-- > > :m +XMonad.Core   -- load the xmonad core
+-- > > :m +XMonad.Layout.Grid  -- load whatever module you want to use
+-- > > description Grid  -- find out what it's called
+-- > "Grid"
+--
+-- As yet another (possibly easier) alternative, you can use the
+-- "XMonad.Layout.Renamed" module (also in @xmonad-contrib@) to give
+-- custom names to your layouts, and use those.
+--
+-- For example, if you want to jump directly to the 'Full' layout you
+-- can do
+--
+-- > , ((modm .|. controlMask, xK_f), sendMessage $ JumpToLayout "Full")
+--
+newtype JumpToLayout = JumpToLayout String
+instance Message JumpToLayout
+
 -- | The layout choice combinator
 (|||) :: l a -> r a -> Choose l r a
-(|||) = Choose L
+(|||) = Choose CL
 infixr 5 |||
 
 -- | A layout that allows users to switch between various layout options.
-data Choose l r a = Choose LR (l a) (r a) deriving (Read, Show)
+data Choose l r a = Choose CLR (l a) (r a) deriving (Read, Show)
 
--- | Are we on the left or right sub-layout?
-data LR = L | R deriving (Read, Show, Eq)
+-- | Choose the current sub-layout (left or right) in 'Choose'.
+data CLR = CL | CR deriving (Read, Show, Eq)
 
-data NextNoWrap = NextNoWrap deriving (Eq, Show, Typeable)
+data NextNoWrap = NextNoWrap deriving (Eq, Show)
 instance Message NextNoWrap
 
 -- | A small wrapper around handleMessage, as it is tedious to write
@@ -159,26 +196,26 @@ handle l m = handleMessage l (SomeMessage m)
 -- new structure if any fields have changed, and performs any necessary cleanup
 -- on newly non-visible layouts.
 choose :: (LayoutClass l a, LayoutClass r a)
-       => Choose l r a-> LR -> Maybe (l a) -> Maybe (r a) -> X (Maybe (Choose l r a))
+       => Choose l r a -> CLR -> Maybe (l a) -> Maybe (r a) -> X (Maybe (Choose l r a))
 choose (Choose d _ _) d' Nothing Nothing | d == d' = return Nothing
 choose (Choose d l r) d' ml      mr = f lr
  where
     (l', r') = (fromMaybe l ml, fromMaybe r mr)
     lr       = case (d, d') of
-                    (L, R) -> (hide l'  , return r')
-                    (R, L) -> (return l', hide r'  )
-                    (_, _) -> (return l', return r')
-    f (x,y)  = fmap Just $ liftM2 (Choose d') x y
-    hide x   = fmap (fromMaybe x) $ handle x Hide
+                    (CL, CR) -> (hide l'  , return r')
+                    (CR, CL) -> (return l', hide r'  )
+                    (_ , _ ) -> (return l', return r')
+    f (x,y)  = Just <$> liftM2 (Choose d') x y
+    hide x   = fromMaybe x <$> handle x Hide
 
 instance (LayoutClass l a, LayoutClass r a) => LayoutClass (Choose l r) a where
-    runLayout (W.Workspace i (Choose L l r) ms) =
-        fmap (second . fmap $ flip (Choose L) r) . runLayout (W.Workspace i l ms)
-    runLayout (W.Workspace i (Choose R l r) ms) =
-        fmap (second . fmap $ Choose R l) . runLayout (W.Workspace i r ms)
+    runLayout (W.Workspace i (Choose CL l r) ms) =
+        fmap (second . fmap $ flip (Choose CL) r) . runLayout (W.Workspace i l ms)
+    runLayout (W.Workspace i (Choose CR l r) ms) =
+        fmap (second . fmap $ Choose CR l) . runLayout (W.Workspace i r ms)
 
-    description (Choose L l _) = description l
-    description (Choose R _ r) = description r
+    description (Choose CL l _) = description l
+    description (Choose CR _ r) = description r
 
     handleMessage lr m | Just NextLayout <- fromMessage m = do
         mlr' <- handle lr NextNoWrap
@@ -186,25 +223,36 @@ instance (LayoutClass l a, LayoutClass r a) => LayoutClass (Choose l r) a where
 
     handleMessage c@(Choose d l r) m | Just NextNoWrap <- fromMessage m =
         case d of
-            L -> do
+            CL -> do
                 ml <- handle l NextNoWrap
                 case ml of
-                    Just _  -> choose c L ml Nothing
-                    Nothing -> choose c R Nothing =<< handle r FirstLayout
+                    Just _  -> choose c CL ml Nothing
+                    Nothing -> choose c CR Nothing =<< handle r FirstLayout
 
-            R -> choose c R Nothing =<< handle r NextNoWrap
+            CR -> choose c CR Nothing =<< handle r NextNoWrap
 
     handleMessage c@(Choose _ l _) m | Just FirstLayout <- fromMessage m =
-        flip (choose c L) Nothing =<< handle l FirstLayout
+        flip (choose c CL) Nothing =<< handle l FirstLayout
 
     handleMessage c@(Choose d l r) m | Just ReleaseResources <- fromMessage m =
         join $ liftM2 (choose c d) (handle l ReleaseResources) (handle r ReleaseResources)
 
+    handleMessage c@(Choose d l r) m | Just e@DestroyWindowEvent{} <- fromMessage m =
+        join $ liftM2 (choose c d) (handle l e) (handle r e)
+
+    handleMessage c@(Choose d l r) m | Just (JumpToLayout desc) <- fromMessage m = do
+        ml <- handleMessage l m
+        mr <- handleMessage r m
+        let md | desc == description (fromMaybe l ml) = CL
+               | desc == description (fromMaybe r mr) = CR
+               | otherwise = d
+        choose c md ml mr
+
     handleMessage c@(Choose d l r) m = do
         ml' <- case d of
-                L -> handleMessage l m
-                R -> return Nothing
+                CL -> handleMessage l m
+                CR -> return Nothing
         mr' <- case d of
-                L -> return Nothing
-                R -> handleMessage r m
+                CL -> return Nothing
+                CR -> handleMessage r m
         choose c d ml' mr'

src/XMonad/Main.hs

@@ -1,4 +1,6 @@
-{-# LANGUAGE MultiParamTypeClasses, FlexibleContexts #-}
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE MultiParamTypeClasses #-}
+
 ----------------------------------------------------------------------------
 -- |
 -- Module      :  XMonad.Main
@@ -13,18 +15,19 @@
 --
 -----------------------------------------------------------------------------
 
-module XMonad.Main (xmonad, launch) where
+module XMonad.Main (xmonad, buildLaunch, launch) where
 
 import System.Locale.SetLocale
-import qualified Control.Exception.Extensible as E
+import qualified Control.Exception as E
 import Data.Bits
 import Data.List ((\\))
-import Data.Function
+import Data.Foldable (traverse_)
 import qualified Data.Map as M
 import qualified Data.Set as S
 import Control.Monad.Reader
 import Control.Monad.State
-import Data.Maybe (fromMaybe)
+import Control.Monad (filterM, guard, unless, void, when)
+import Data.Maybe (fromMaybe, isJust)
 import Data.Monoid (getAll)
 
 import Graphics.X11.Xlib hiding (refreshKeyboardMapping)
@@ -39,7 +42,7 @@ import XMonad.Operations
 import System.IO
 import System.Directory
 import System.Info
-import System.Environment
+import System.Environment (getArgs, getProgName, withArgs)
 import System.Posix.Process (executeFile)
 import System.Exit (exitFailure)
 import System.FilePath
@@ -48,6 +51,7 @@ import Paths_xmonad (version)
 import Data.Version (showVersion)
 
 import Graphics.X11.Xinerama (compiledWithXinerama)
+import Graphics.X11.Xrandr (xrrQueryExtension, xrrUpdateConfiguration)
 
 ------------------------------------------------------------------------
 
@@ -59,17 +63,17 @@ xmonad :: (LayoutClass l Window, Read (l Window)) => XConfig l -> IO ()
 xmonad conf = do
     installSignalHandlers -- important to ignore SIGCHLD to avoid zombies
 
+    dirs <- getDirectories
     let launch' args = do
-              catchIO buildLaunch
-              conf' @ XConfig { layoutHook = Layout l }
+              catchIO (buildLaunch dirs)
+              conf'@XConfig { layoutHook = Layout l }
                   <- handleExtraArgs conf args conf{ layoutHook = Layout (layoutHook conf) }
-              withArgs [] $ launch (conf' { layoutHook = l })
+              withArgs [] $ launch (conf' { layoutHook = l }) dirs
 
     args <- getArgs
     case args of
-        ("--resume": ws : xs : args') -> migrateState ws xs >> launch' args'
         ["--help"]            -> usage
-        ["--recompile"]       -> recompile True >>= flip unless exitFailure
+        ["--recompile"]       -> recompile dirs True >>= flip unless exitFailure
         ["--restart"]         -> sendRestart
         ["--version"]         -> putStrLn $ unwords shortVersion
         ["--verbose-version"] -> putStrLn . unwords $ shortVersion ++ longVersion
@@ -86,14 +90,14 @@ usage :: IO ()
 usage = do
     self <- getProgName
     putStr . unlines $
-        concat ["Usage: ", self, " [OPTION]"] :
-        "Options:" :
-        "  --help                       Print this message" :
-        "  --version                    Print the version number" :
-        "  --recompile                  Recompile your ~/.xmonad/xmonad.hs" :
-        "  --replace                    Replace the running window manager with xmonad" :
-        "  --restart                    Request a running xmonad process to restart" :
-        []
+        [ "Usage: " <> self <> " [OPTION]"
+        , "Options:"
+        , "  --help                       Print this message"
+        , "  --version                    Print the version number"
+        , "  --recompile                  Recompile your xmonad.hs"
+        , "  --replace                    Replace the running window manager with xmonad"
+        , "  --restart                    Request a running xmonad process to restart"
+        ]
 
 -- | Build the xmonad configuration file with ghc, then execute it.
 -- If there are no errors, this function does not return.  An
@@ -111,40 +115,21 @@ usage = do
 --
 --   * Missing XMonad\/XMonadContrib modules due to ghc upgrade
 --
-buildLaunch ::  IO ()
-buildLaunch = do
+buildLaunch :: Directories -> IO ()
+buildLaunch dirs = do
     whoami <- getProgName
-    let compiledConfig = "xmonad-"++arch++"-"++os
+    let bin = binFileName dirs
+    let compiledConfig = takeFileName bin
     unless (whoami == compiledConfig) $ do
       trace $ concat
-        [ "XMonad is recompiling and replacing itself another XMonad process because the current process is called "
+        [ "XMonad is recompiling and replacing itself with another XMonad process because the current process is called "
         , show whoami
         , " but the compiled configuration should be called "
         , show compiledConfig
         ]
-      recompile False
-      dir  <- getXMonadDataDir
+      recompile dirs False
       args <- getArgs
-      executeFile (dir </> compiledConfig) False args Nothing
-
-sendRestart :: IO ()
-sendRestart = do
-    dpy <- openDisplay ""
-    rw <- rootWindow dpy $ defaultScreen dpy
-    xmonad_restart <- internAtom dpy "XMONAD_RESTART" False
-    allocaXEvent $ \e -> do
-        setEventType e clientMessage
-        setClientMessageEvent e rw xmonad_restart 32 0 currentTime
-        sendEvent dpy rw False structureNotifyMask e
-    sync dpy False
-
--- | a wrapper for 'replace'
-sendReplace :: IO ()
-sendReplace = do
-    dpy <- openDisplay ""
-    let dflt = defaultScreen dpy
-    rootw  <- rootWindow dpy dflt
-    replace dpy dflt rootw
+      executeFile bin False args Nothing
 
 -- | Entry point into xmonad for custom builds.
 --
@@ -166,8 +151,8 @@ sendReplace = do
 -- function instead of 'xmonad'.  You probably also want to have a key
 -- binding to the 'XMonad.Operations.restart` function that restarts
 -- your custom binary with the resume flag set to @True@.
-launch :: (LayoutClass l Window, Read (l Window)) => XConfig l -> IO ()
-launch initxmc = do
+launch :: (LayoutClass l Window, Read (l Window)) => XConfig l -> Directories -> IO ()
+launch initxmc drs = do
     -- setup locale information from environment
     setLocale LC_ALL (Just "")
     -- ignore SIGPIPE and SIGCHLD
@@ -192,12 +177,12 @@ launch initxmc = do
 
     xinesc <- getCleanedScreenInfo dpy
 
-    nbc    <- do v            <- initColor dpy $ normalBorderColor  xmc
-                 ~(Just nbc_) <- initColor dpy $ normalBorderColor Default.def
+    nbc    <- do v         <- initColor dpy $ normalBorderColor  xmc
+                 Just nbc_ <- initColor dpy $ normalBorderColor Default.def
                  return (fromMaybe nbc_ v)
 
     fbc    <- do v <- initColor dpy $ focusedBorderColor xmc
-                 ~(Just fbc_)  <- initColor dpy $ focusedBorderColor Default.def
+                 Just fbc_ <- initColor dpy $ focusedBorderColor Default.def
                  return (fromMaybe fbc_ v)
 
     hSetBuffering stdout NoBuffering
@@ -216,7 +201,9 @@ launch initxmc = do
             , buttonActions = mouseBindings xmc xmc
             , mouseFocused  = False
             , mousePosition = Nothing
-            , currentEvent  = Nothing }
+            , currentEvent  = Nothing
+            , directories   = drs
+            }
 
         st = XState
             { windowset       = initialWinset
@@ -231,7 +218,7 @@ launch initxmc = do
         runX cf st $ do
             -- check for serialized state in a file.
             serializedSt <- do
-                path <- stateFileName
+                path <- asks $ stateFileName . directories
                 exists <- io (doesFileExist path)
                 if exists then readStateFile initxmc else return Nothing
 
@@ -239,7 +226,7 @@ launch initxmc = do
             let extst = maybe M.empty extensibleState serializedSt
             modify (\s -> s {extensibleState = extst})
 
-            setNumlockMask
+            cacheNumlockMask
             grabKeys
             grabButtons
 
@@ -260,8 +247,12 @@ launch initxmc = do
 
             userCode $ startupHook initxmc
 
+            rrData <- io $ xrrQueryExtension dpy
+
             -- main loop, for all you HOF/recursion fans out there.
-            forever $ prehandle =<< io (nextEvent dpy e >> getEvent e)
+            -- forever $ prehandle =<< io (nextEvent dpy e >> rrUpdate e >> getEvent e)
+            -- sadly, 9.2.{1,2,3} join points mishandle the above and trash the heap (see #389)
+            mainLoop dpy e rrData
 
     return ()
       where
@@ -272,6 +263,8 @@ launch initxmc = do
                       in local (\c -> c { mousePosition = mouse, currentEvent = Just e }) (handleWithHook e)
         evs = [ keyPress, keyRelease, enterNotify, leaveNotify
               , buttonPress, buttonRelease]
+        rrUpdate e r = when (isJust r) (void (xrrUpdateConfiguration e))
+        mainLoop d e r = io (nextEvent d e >> rrUpdate e r >> getEvent e) >>= prehandle >> mainLoop d e r
 
 
 -- | Runs handleEventHook from the configuration and runs the default handler
@@ -310,16 +303,21 @@ handle (MapRequestEvent    {ev_window = w}) = withDisplay $ \dpy -> do
 
 -- window destroyed, unmanage it
 -- window gone,      unmanage it
-handle (DestroyWindowEvent {ev_window = w}) = whenX (isClient w) $ do
+-- broadcast to layouts
+handle e@(DestroyWindowEvent {ev_window = w}) = do
+  whenX (isClient w) $ do
     unmanage w
     modify (\s -> s { mapped       = S.delete w (mapped s)
                     , waitingUnmap = M.delete w (waitingUnmap s)})
+  -- the window is already unmanged, but we broadcast the event to all layouts
+  -- to trigger garbage-collection in case they hold window-specific resources
+  broadcastMessage e
 
 -- We track expected unmap events in waitingUnmap.  We ignore this event unless
 -- it is synthetic or we are not expecting an unmap notification from a window.
 handle (UnmapEvent {ev_window = w, ev_send_event = synthetic}) = whenX (isClient w) $ do
     e <- gets (fromMaybe 0 . M.lookup w . waitingUnmap)
-    if (synthetic || e == 0)
+    if synthetic || e == 0
         then unmanage w
         else modify (\s -> s { waitingUnmap = M.update mpred w (waitingUnmap s) })
  where mpred 1 = Nothing
@@ -329,7 +327,7 @@ handle (UnmapEvent {ev_window = w, ev_send_event = synthetic}) = whenX (isClient
 handle e@(MappingNotifyEvent {}) = do
     io $ refreshKeyboardMapping e
     when (ev_request e `elem` [mappingKeyboard, mappingModifier]) $ do
-        setNumlockMask
+        cacheNumlockMask
         grabKeys
 
 -- handle button release, which may finish dragging.
@@ -417,7 +415,7 @@ handle event@(PropertyEvent { ev_event_type = t, ev_atom = a })
 
 handle e@ClientMessageEvent { ev_message_type = mt } = do
     a <- getAtom "XMONAD_RESTART"
-    if (mt == a)
+    if mt == a
         then restart "xmonad" True
         else broadcastMessage e
 
@@ -448,35 +446,14 @@ scan dpy rootw = do
         skip :: E.SomeException -> IO Bool
         skip _ = return False
 
-setNumlockMask :: X ()
-setNumlockMask = do
-    dpy <- asks display
-    ms <- io $ getModifierMapping dpy
-    xs <- sequence [ do
-                        ks <- io $ keycodeToKeysym dpy kc 0
-                        if ks == xK_Num_Lock
-                            then return (setBit 0 (fromIntegral m))
-                            else return (0 :: KeyMask)
-                        | (m, kcs) <- ms, kc <- kcs, kc /= 0]
-    modify (\s -> s { numberlockMask = foldr (.|.) 0 xs })
-
 -- | Grab the keys back
 grabKeys :: X ()
 grabKeys = do
     XConf { display = dpy, theRoot = rootw } <- ask
-    let grab kc m = io $ grabKey dpy kc m rootw True grabModeAsync grabModeAsync
-        (minCode, maxCode) = displayKeycodes dpy
-        allCodes = [fromIntegral minCode .. fromIntegral maxCode]
     io $ ungrabKey dpy anyKey anyModifier rootw
-    ks <- asks keyActions
-    -- build a map from keysyms to lists of keysyms (doing what
-    -- XGetKeyboardMapping would do if the X11 package bound it)
-    syms <- forM allCodes $ \code -> io (keycodeToKeysym dpy code 0)
-    let keysymMap = M.fromListWith (++) (zip syms [[code] | code <- allCodes])
-        keysymToKeycodes sym = M.findWithDefault [] sym keysymMap
-    forM_ (M.keys ks) $ \(mask,sym) ->
-         forM_ (keysymToKeycodes sym) $ \kc ->
-              mapM_ (grab kc . (mask .|.)) =<< extraModifiers
+    let grab :: (KeyMask, KeyCode) -> X ()
+        grab (km, kc) = io $ grabKey dpy kc km rootw True grabModeAsync grabModeAsync
+    traverse_ grab =<< mkGrabs =<< asks (M.keys . keyActions)
 
 -- | Grab the buttons
 grabButtons :: X ()
@@ -487,37 +464,4 @@ grabButtons = do
     io $ ungrabButton dpy anyButton anyModifier rootw
     ems <- extraModifiers
     ba <- asks buttonActions
-    mapM_ (\(m,b) -> mapM_ (grab b . (m .|.)) ems) (M.keys $ ba)
-
--- | @replace@ to signals compliant window managers to exit.
-replace :: Display -> ScreenNumber -> Window -> IO ()
-replace dpy dflt rootw = do
-    -- check for other WM
-    wmSnAtom <- internAtom dpy ("WM_S" ++ show dflt) False
-    currentWmSnOwner <- xGetSelectionOwner dpy wmSnAtom
-    when (currentWmSnOwner /= 0) $ do
-        -- prepare to receive destroyNotify for old WM
-        selectInput dpy currentWmSnOwner structureNotifyMask
-
-        -- create off-screen window
-        netWmSnOwner <- allocaSetWindowAttributes $ \attributes -> do
-            set_override_redirect attributes True
-            set_event_mask attributes propertyChangeMask
-            let screen = defaultScreenOfDisplay dpy
-                visual = defaultVisualOfScreen screen
-                attrmask = cWOverrideRedirect .|. cWEventMask
-            createWindow dpy rootw (-100) (-100) 1 1 0 copyFromParent copyFromParent visual attrmask attributes
-
-        -- try to acquire wmSnAtom, this should signal the old WM to terminate
-        xSetSelectionOwner dpy wmSnAtom netWmSnOwner currentTime
-
-        -- SKIPPED: check if we acquired the selection
-        -- SKIPPED: send client message indicating that we are now the WM
-
-        -- wait for old WM to go away
-        fix $ \again -> do
-            evt <- allocaXEvent $ \event -> do
-                windowEvent dpy currentWmSnOwner structureNotifyMask event
-                get_EventType event
-
-            when (evt /= destroyNotify) again
+    mapM_ (\(m,b) -> mapM_ (grab b . (m .|.)) ems) (M.keys ba)

src/XMonad/ManageHook.hs

@@ -1,5 +1,3 @@
-{-# LANGUAGE GeneralizedNewtypeDeriving #-}
-
 -----------------------------------------------------------------------------
 -- |
 -- Module      :  XMonad.ManageHook
@@ -8,7 +6,6 @@
 --
 -- Maintainer  :  spencerjanssen@gmail.com
 -- Stability   :  unstable
--- Portability :  not portable, uses cunning newtype deriving
 --
 -- An EDSL for ManageHooks
 --
@@ -21,13 +18,13 @@ module XMonad.ManageHook where
 import XMonad.Core
 import Graphics.X11.Xlib.Extras
 import Graphics.X11.Xlib (Display, Window, internAtom, wM_NAME)
-import Control.Exception.Extensible (bracket, SomeException(..))
-import qualified Control.Exception.Extensible as E
+import Control.Exception (bracket, SomeException(..))
+import qualified Control.Exception as E
 import Control.Monad.Reader
 import Data.Maybe
 import Data.Monoid
 import qualified XMonad.StackSet as W
-import XMonad.Operations (floatLocation, reveal)
+import XMonad.Operations (floatLocation, reveal, isFixedSizeOrTransient)
 
 -- | Lift an 'X' action to a 'Query'.
 liftX :: X a -> Query a
@@ -61,11 +58,11 @@ infixr 3 <&&>, <||>
 
 -- | '&&' lifted to a 'Monad'.
 (<&&>) :: Monad m => m Bool -> m Bool -> m Bool
-(<&&>) = liftM2 (&&)
+x <&&> y = ifM x y (pure False)
 
 -- | '||' lifted to a 'Monad'.
 (<||>) :: Monad m => m Bool -> m Bool -> m Bool
-(<||>) = liftM2 (||)
+x <||> y = ifM x (pure True) y
 
 -- | Return the window title.
 title :: Query String
@@ -76,10 +73,11 @@ title = ask >>= \w -> liftX $ do
             (internAtom d "_NET_WM_NAME" False >>= getTextProperty d w)
                 `E.catch` \(SomeException _) -> getTextProperty d w wM_NAME
         extract prop = do l <- wcTextPropertyToTextList d prop
-                          return $ if null l then "" else head l
+                          return $ fromMaybe "" $ listToMaybe l
     io $ bracket getProp (xFree . tp_value) extract `E.catch` \(SomeException _) -> return ""
 
--- | Return the application name.
+-- | Return the application name; i.e., the /first/ string returned by
+-- @WM_CLASS@.
 appName :: Query String
 appName = ask >>= (\w -> liftX $ withDisplay $ \d -> fmap resName $ io $ getClassHint d w)
 
@@ -87,14 +85,15 @@ appName = ask >>= (\w -> liftX $ withDisplay $ \d -> fmap resName $ io $ getClas
 resource :: Query String
 resource = appName
 
--- | Return the resource class.
+-- | Return the resource class; i.e., the /second/ string returned by
+-- @WM_CLASS@.
 className :: Query String
 className = ask >>= (\w -> liftX $ withDisplay $ \d -> fmap resClass $ io $ getClassHint d w)
 
 -- | A query that can return an arbitrary X property of type 'String',
 --   identified by name.
 stringProperty :: String -> Query String
-stringProperty p = ask >>= (\w -> liftX $ withDisplay $ \d -> fmap (fromMaybe "") $ getStringProperty d w p)
+stringProperty p = ask >>= (\w -> liftX $ withDisplay $ \d -> fromMaybe "" <$> getStringProperty d w p)
 
 getStringProperty :: Display -> Window -> String -> X (Maybe String)
 getStringProperty d w p = do
@@ -102,6 +101,10 @@ getStringProperty d w p = do
   md <- io $ getWindowProperty8 d a w
   return $ fmap (map (toEnum . fromIntegral)) md
 
+-- | Return whether the window will be a floating window or not
+willFloat :: Query Bool
+willFloat = ask >>= \w -> liftX $ withDisplay $ \d -> isFixedSizeOrTransient d w
+
 -- | Modify the 'WindowSet' with a pure function.
 doF :: (s -> s) -> Query (Endo s)
 doF = return . Endo

src/XMonad/Operations.hs

@@ -1,5 +1,10 @@
-{-# OPTIONS_GHC -fno-warn-orphans #-}
-{-# LANGUAGE FlexibleContexts, FlexibleInstances, MultiParamTypeClasses, PatternGuards, TypeSynonymInstances #-}
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE FlexibleInstances #-}
+{-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE MultiParamTypeClasses #-}
+{-# LANGUAGE PatternGuards #-}
+{-# LANGUAGE ScopedTypeVariables #-}
+
 -- --------------------------------------------------------------------------
 -- |
 -- Module      :  XMonad.Operations
@@ -8,31 +13,69 @@
 --
 -- Maintainer  :  dons@cse.unsw.edu.au
 -- Stability   :  unstable
--- Portability :  not portable, Typeable deriving, mtl, posix
+-- Portability :  not portable, mtl, posix
 --
--- Operations.
+-- Operations. A module for functions that don't cleanly fit anywhere else.
 --
 -----------------------------------------------------------------------------
 
-module XMonad.Operations where
+module XMonad.Operations (
+    -- * Manage One Window
+    manage, unmanage, killWindow, kill, isClient,
+    setInitialProperties, setWMState, setWindowBorderWithFallback,
+    hide, reveal, tileWindow,
+    setTopFocus, focus, isFixedSizeOrTransient,
+
+    -- * Manage Windows
+    windows, refresh, rescreen, modifyWindowSet, windowBracket, windowBracket_, clearEvents, getCleanedScreenInfo,
+    withFocused, withUnfocused,
+
+    -- * Keyboard and Mouse
+    cleanMask, extraModifiers,
+    mouseDrag, mouseMoveWindow, mouseResizeWindow,
+    setButtonGrab, setFocusX, cacheNumlockMask, mkGrabs, unGrab,
+
+    -- * Messages
+    sendMessage, broadcastMessage, sendMessageWithNoRefresh,
+    sendRestart, sendReplace,
+
+    -- * Save and Restore State
+    StateFile (..), writeStateToFile, readStateFile, restart,
+
+    -- * Floating Layer
+    float, floatLocation,
+
+    -- * Window Size Hints
+    D, mkAdjust, applySizeHints, applySizeHints', applySizeHintsContents,
+    applyAspectHint, applyResizeIncHint, applyMaxSizeHint,
+
+    -- * Rectangles
+    containedIn, nubScreens, pointWithin, scaleRationalRect,
+
+    -- * Other Utilities
+    initColor, pointScreen, screenWorkspace,
+    setLayout, updateLayout,
+    ) where
 
 import XMonad.Core
 import XMonad.Layout (Full(..))
 import qualified XMonad.StackSet as W
 
 import Data.Maybe
-import Data.Monoid          (Endo(..))
+import Data.Monoid          (Endo(..),Any(..))
 import Data.List            (nub, (\\), find)
-import Data.Bits            ((.|.), (.&.), complement, testBit)
+import Data.Bits            ((.|.), (.&.), complement, setBit, testBit)
+import Data.Function        (on)
 import Data.Ratio
 import qualified Data.Map as M
 import qualified Data.Set as S
 
-import Control.Applicative((<$>), (<*>))
 import Control.Arrow (second)
+import Control.Monad.Fix (fix)
 import Control.Monad.Reader
 import Control.Monad.State
-import qualified Control.Exception.Extensible as C
+import Control.Monad (forM, forM_, guard, join, unless, void, when)
+import qualified Control.Exception as C
 
 import System.IO
 import System.Directory
@@ -42,9 +85,20 @@ import Graphics.X11.Xinerama (getScreenInfo)
 import Graphics.X11.Xlib.Extras
 
 -- ---------------------------------------------------------------------
--- |
 -- Window manager operations
--- manage. Add a new window to be managed in the current workspace.
+
+-- | Detect whether a window has fixed size or is transient. This check
+-- can be used to determine whether the window should be floating or not
+--
+isFixedSizeOrTransient :: Display -> Window -> X Bool
+isFixedSizeOrTransient d w = do
+    sh <- io $ getWMNormalHints d w
+    let isFixedSize = isJust (sh_min_size sh) && sh_min_size sh == sh_max_size sh
+    isTransient <- isJust <$> io (getTransientForHint d w)
+    return (isFixedSize || isTransient)
+
+-- |
+-- Add a new window to be managed in the current workspace.
 -- Bring it into focus.
 --
 -- Whether the window is already managed, or not, it is mapped, has its
@@ -52,10 +106,8 @@ import Graphics.X11.Xlib.Extras
 --
 manage :: Window -> X ()
 manage w = whenX (not <$> isClient w) $ withDisplay $ \d -> do
-    sh <- io $ getWMNormalHints d w
 
-    let isFixedSize = sh_min_size sh /= Nothing && sh_min_size sh == sh_max_size sh
-    isTransient <- isJust <$> io (getTransientForHint d w)
+    shouldFloat <- isFixedSizeOrTransient d w
 
     rr <- snd `fmap` floatLocation w
     -- ensure that float windows don't go over the edge of the screen
@@ -63,15 +115,15 @@ manage w = whenX (not <$> isClient w) $ withDisplay $ \d -> do
                                               = W.RationalRect (0.5 - wid/2) (0.5 - h/2) wid h
         adjust r = r
 
-        f ws | isFixedSize || isTransient = W.float w (adjust rr) . W.insertUp w . W.view i $ ws
-             | otherwise                  = W.insertUp w ws
+        f ws | shouldFloat = W.float w (adjust rr) . W.insertUp w . W.view i $ ws
+             | otherwise   = W.insertUp w ws
             where i = W.tag $ W.workspace $ W.current ws
 
     mh <- asks (manageHook . config)
     g <- appEndo <$> userCodeDef (Endo id) (runQuery mh w)
     windows (g . f)
 
--- | unmanage. A window no longer exists, remove it from the window
+-- | A window no longer exists; remove it from the window
 -- list, on whatever workspace it is.
 --
 unmanage :: Window -> X ()
@@ -91,9 +143,9 @@ killWindow w = withDisplay $ \d -> do
     io $ if wmdelt `elem` protocols
         then allocaXEvent $ \ev -> do
                 setEventType ev clientMessage
-                setClientMessageEvent ev w wmprot 32 wmdelt 0
+                setClientMessageEvent ev w wmprot 32 wmdelt currentTime
                 sendEvent d w False noEventMask ev
-        else killClient d w >> return ()
+        else void (killClient d w)
 
 -- | Kill the currently focused client.
 kill :: X ()
@@ -102,7 +154,7 @@ kill = withFocused killWindow
 -- ---------------------------------------------------------------------
 -- Managing windows
 
--- | windows. Modify the current window list with a pure function, and refresh
+-- | Modify the current window list with a pure function, and refresh
 windows :: (WindowSet -> WindowSet) -> X ()
 windows f = do
     XState { windowset = old } <- get
@@ -144,7 +196,8 @@ windows f = do
 
         let m   = W.floating ws
             flt = [(fw, scaleRationalRect viewrect r)
-                    | fw <- filter (flip M.member m) (W.index this)
+                    | fw <- filter (`M.member` m) (W.index this)
+                    , fw `notElem` vis
                     , Just r <- [M.lookup fw m]]
             vs = flt ++ rs
 
@@ -170,38 +223,58 @@ windows f = do
     -- all windows that are no longer in the windowset are marked as
     -- withdrawn, it is important to do this after the above, otherwise 'hide'
     -- will overwrite withdrawnState with iconicState
-    mapM_ (flip setWMState withdrawnState) (W.allWindows old \\ W.allWindows ws)
+    mapM_ (`setWMState` withdrawnState) (W.allWindows old \\ W.allWindows ws)
 
     isMouseFocused <- asks mouseFocused
     unless isMouseFocused $ clearEvents enterWindowMask
     asks (logHook . config) >>= userCodeDef ()
 
+-- | Modify the @WindowSet@ in state with no special handling.
+modifyWindowSet :: (WindowSet -> WindowSet) -> X ()
+modifyWindowSet f = modify $ \xst -> xst { windowset = f (windowset xst) }
+
+-- | Perform an @X@ action and check its return value against a predicate p.
+-- If p holds, unwind changes to the @WindowSet@ and replay them using @windows@.
+windowBracket :: (a -> Bool) -> X a -> X a
+windowBracket p action = withWindowSet $ \old -> do
+  a <- action
+  when (p a) . withWindowSet $ \new -> do
+    modifyWindowSet $ const old
+    windows         $ const new
+  return a
+
+-- | Perform an @X@ action. If it returns @Any True@, unwind the
+-- changes to the @WindowSet@ and replay them using @windows@. This is
+-- a version of @windowBracket@ that discards the return value and
+-- handles an @X@ action that reports its need for refresh via @Any@.
+windowBracket_ :: X Any -> X ()
+windowBracket_ = void . windowBracket getAny
+
 -- | Produce the actual rectangle from a screen and a ratio on that screen.
 scaleRationalRect :: Rectangle -> W.RationalRect -> Rectangle
 scaleRationalRect (Rectangle sx sy sw sh) (W.RationalRect rx ry rw rh)
  = Rectangle (sx + scale sw rx) (sy + scale sh ry) (scale sw rw) (scale sh rh)
  where scale s r = floor (toRational s * r)
 
--- | setWMState.  set the WM_STATE property
+-- | Set a window's WM_STATE property.
 setWMState :: Window -> Int -> X ()
 setWMState w v = withDisplay $ \dpy -> do
     a <- atom_WM_STATE
     io $ changeProperty32 dpy w a a propModeReplace [fromIntegral v, fromIntegral none]
 
--- | Set the border color using the window's color map, if possible,
--- otherwise fallback to the color in @Pixel@.
+-- | Set the border color using the window's color map, if possible;
+-- otherwise fall back to the color in @Pixel@.
 setWindowBorderWithFallback :: Display -> Window -> String -> Pixel -> X ()
 setWindowBorderWithFallback dpy w color basic = io $
     C.handle fallback $ do
       wa <- getWindowAttributes dpy w
-      pixel <- color_pixel . fst <$> allocNamedColor dpy (wa_colormap wa) color
+      pixel <- setPixelSolid . color_pixel . fst <$> allocNamedColor dpy (wa_colormap wa) color
       setWindowBorder dpy w pixel
   where
     fallback :: C.SomeException -> IO ()
-    fallback e = do hPrint stderr e >> hFlush stderr
-                    setWindowBorder dpy w basic
+    fallback _ = setWindowBorder dpy w basic
 
--- | hide. Hide a window by unmapping it, and setting Iconified.
+-- | Hide a window by unmapping it and setting Iconified.
 hide :: Window -> X ()
 hide w = whenX (gets (S.member w . mapped)) $ withDisplay $ \d -> do
     cMask <- asks $ clientMask . config
@@ -214,15 +287,15 @@ hide w = whenX (gets (S.member w . mapped)) $ withDisplay $ \d -> do
     modify (\s -> s { waitingUnmap = M.insertWith (+) w 1 (waitingUnmap s)
                     , mapped       = S.delete w (mapped s) })
 
--- | reveal. Show a window by mapping it and setting Normal
--- this is harmless if the window was already visible
+-- | Show a window by mapping it and setting Normal.
+-- This is harmless if the window was already visible.
 reveal :: Window -> X ()
 reveal w = withDisplay $ \d -> do
     setWMState w normalState
     io $ mapWindow d w
     whenX (isClient w) $ modify (\s -> s { mapped = S.insert w (mapped s) })
 
--- | Set some properties when we initially gain control of a window
+-- | Set some properties when we initially gain control of a window.
 setInitialProperties :: Window -> X ()
 setInitialProperties w = asks normalBorder >>= \nb -> withDisplay $ \d -> do
     setWMState w iconicState
@@ -233,7 +306,7 @@ setInitialProperties w = asks normalBorder >>= \nb -> withDisplay $ \d -> do
     -- required by the border setting in 'windows'
     io $ setWindowBorder d w nb
 
--- | refresh. Render the currently visible workspaces, as determined by
+-- | Render the currently visible workspaces, as determined by
 -- the 'StackSet'. Also, set focus to the focused window.
 --
 -- This is our 'view' operation (MVC), in that it pretty prints our model
@@ -242,7 +315,7 @@ setInitialProperties w = asks normalBorder >>= \nb -> withDisplay $ \d -> do
 refresh :: X ()
 refresh = windows id
 
--- | clearEvents.  Remove all events of a given type from the event queue.
+-- | Remove all events of a given type from the event queue.
 clearEvents :: EventMask -> X ()
 clearEvents mask = withDisplay $ \d -> io $ do
     sync d False
@@ -250,8 +323,8 @@ clearEvents mask = withDisplay $ \d -> io $ do
         more <- checkMaskEvent d mask p
         when more again -- beautiful
 
--- | tileWindow. Moves and resizes w such that it fits inside the given
--- rectangle, including its border.
+-- | Move and resize @w@ such that it fits inside the given rectangle,
+-- including its border.
 tileWindow :: Window -> Rectangle -> X ()
 tileWindow w r = withDisplay $ \d -> withWindowAttributes d w $ \wa -> do
     -- give all windows at least 1x1 pixels
@@ -278,27 +351,28 @@ containedIn r1@(Rectangle x1 y1 w1 h1) r2@(Rectangle x2 y2 w2 h2)
 nubScreens :: [Rectangle] -> [Rectangle]
 nubScreens xs = nub . filter (\x -> not $ any (x `containedIn`) xs) $ xs
 
--- | Cleans the list of screens according to the rules documented for
+-- | Clean the list of screens according to the rules documented for
 -- nubScreens.
 getCleanedScreenInfo :: MonadIO m => Display -> m [Rectangle]
 getCleanedScreenInfo = io .  fmap nubScreens . getScreenInfo
 
--- | rescreen.  The screen configuration may have changed (due to
--- xrandr), update the state and refresh the screen, and reset the gap.
+-- | The screen configuration may have changed (due to -- xrandr),
+-- update the state and refresh the screen, and reset the gap.
 rescreen :: X ()
-rescreen = do
-    xinesc <- withDisplay getCleanedScreenInfo
-
-    windows $ \ws@(W.StackSet { W.current = v, W.visible = vs, W.hidden = hs }) ->
-        let (xs, ys) = splitAt (length xinesc) $ map W.workspace (v:vs) ++ hs
-            (a:as)   = zipWith3 W.Screen xs [0..] $ map SD xinesc
-        in  ws { W.current = a
-               , W.visible = as
-               , W.hidden  = ys }
+rescreen = withDisplay getCleanedScreenInfo >>= \case
+    [] -> trace "getCleanedScreenInfo returned []"
+    xinesc:xinescs ->
+        windows $ \ws@W.StackSet{ W.current = v, W.visible = vs, W.hidden = hs } ->
+            let (xs, ys) = splitAt (length xinescs) (map W.workspace vs ++ hs)
+                a = W.Screen (W.workspace v) 0 (SD xinesc)
+                as = zipWith3 W.Screen xs [1..] $ map SD xinescs
+            in  ws { W.current = a
+                   , W.visible = as
+                   , W.hidden  = ys }
 
 -- ---------------------------------------------------------------------
 
--- | setButtonGrab. Tell whether or not to intercept clicks on a given window
+-- | Tell whether or not to intercept clicks on a given window
 setButtonGrab :: Bool -> Window -> X ()
 setButtonGrab grab w = do
     pointerMode <- asks $ \c -> if clickJustFocuses (config c)
@@ -353,7 +427,7 @@ setFocusX w = withWindowSet $ \ws -> do
     currevt <- asks currentEvent
     let inputHintSet = wmh_flags hints `testBit` inputHintBit
 
-    when ((inputHintSet && wmh_input hints) || (not inputHintSet)) $
+    when (inputHintSet && wmh_input hints || not inputHintSet) $
       io $ do setInputFocus dpy w revertToPointerRoot 0
     when (wmtf `elem` protocols) $
       io $ allocaXEvent $ \ev -> do
@@ -361,56 +435,171 @@ setFocusX w = withWindowSet $ \ws -> do
         setClientMessageEvent ev w wmprot 32 wmtf $ maybe currentTime event_time currevt
         sendEvent dpy w False noEventMask ev
         where event_time ev =
-                if (ev_event_type ev) `elem` timedEvents then
+                if ev_event_type ev `elem` timedEvents then
                   ev_time ev
                 else
                   currentTime
               timedEvents = [ keyPress, keyRelease, buttonPress, buttonRelease, enterNotify, leaveNotify, selectionRequest ]
 
+cacheNumlockMask :: X ()
+cacheNumlockMask = do
+    dpy <- asks display
+    ms <- io $ getModifierMapping dpy
+    xs <- sequence [ do ks <- io $ keycodeToKeysym dpy kc 0
+                        if ks == xK_Num_Lock
+                            then return (setBit 0 (fromIntegral m))
+                            else return (0 :: KeyMask)
+                   | (m, kcs) <- ms, kc <- kcs, kc /= 0
+                   ]
+    modify (\s -> s { numberlockMask = foldr (.|.) 0 xs })
+
+-- | Given a list of keybindings, turn the given 'KeySym's into actual
+-- 'KeyCode's and prepare them for grabbing.
+mkGrabs :: [(KeyMask, KeySym)] -> X [(KeyMask, KeyCode)]
+mkGrabs ks = withDisplay $ \dpy -> do
+    let (minCode, maxCode) = displayKeycodes dpy
+        allCodes = [fromIntegral minCode .. fromIntegral maxCode]
+    -- build a map from keysyms to lists of keysyms (doing what
+    -- XGetKeyboardMapping would do if the X11 package bound it)
+    syms <- forM allCodes $ \code -> io (keycodeToKeysym dpy code 0)
+    let -- keycodeToKeysym returns noSymbol for all unbound keycodes,
+        -- and we don't want to grab those whenever someone accidentally
+        -- uses def :: KeySym
+        keysymMap = M.delete noSymbol $
+            M.fromListWith (++) (zip syms [[code] | code <- allCodes])
+        keysymToKeycodes sym = M.findWithDefault [] sym keysymMap
+    extraMods <- extraModifiers
+    pure [ (mask .|. extraMod, keycode)
+         | (mask, sym) <- ks
+         , keycode     <- keysymToKeycodes sym
+         , extraMod    <- extraMods
+         ]
+
+-- | Release XMonad's keyboard grab, so other grabbers can do their thing.
+--
+-- Start a keyboard action with this if it is going to run something
+-- that needs to do a keyboard, pointer, or server grab. For example,
+--
+-- > , ((modm .|. controlMask, xK_p), unGrab >> spawn "scrot")
+--
+-- (Other examples are certain screen lockers and "gksu".)
+-- This avoids needing to insert a pause/sleep before running the
+-- command.
+--
+-- XMonad retains the keyboard grab during key actions because if they
+-- use a submap, they need the keyboard to be grabbed, and if they had
+-- to assert their own grab then the asynchronous nature of X11 allows
+-- race conditions between XMonad, other clients, and the X server that
+-- would cause keys to sometimes be "leaked" to the focused window.
+unGrab :: X ()
+unGrab = withDisplay $ \d -> io $ do
+    ungrabKeyboard d currentTime
+    ungrabPointer  d currentTime
+    sync d False
+
 ------------------------------------------------------------------------
 -- Message handling
 
 -- | Throw a message to the current 'LayoutClass' possibly modifying how we
--- layout the windows, then refresh.
+-- layout the windows, in which case changes are handled through a refresh.
 sendMessage :: Message a => a -> X ()
-sendMessage a = do
-    w <- W.workspace . W.current <$> gets windowset
+sendMessage a = windowBracket_ $ do
+    w <- gets $ W.workspace . W.current . windowset
     ml' <- handleMessage (W.layout w) (SomeMessage a) `catchX` return Nothing
     whenJust ml' $ \l' ->
-        windows $ \ws -> ws { W.current = (W.current ws)
+        modifyWindowSet $ \ws -> ws { W.current = (W.current ws)
                                 { W.workspace = (W.workspace $ W.current ws)
                                   { W.layout = l' }}}
+    return (Any $ isJust ml')
 
 -- | Send a message to all layouts, without refreshing.
 broadcastMessage :: Message a => a -> X ()
 broadcastMessage a = withWindowSet $ \ws -> do
-   let c = W.workspace . W.current $ ws
-       v = map W.workspace . W.visible $ ws
-       h = W.hidden ws
-   mapM_ (sendMessageWithNoRefresh a) (c : v ++ h)
+    -- this is O(n²), but we can't really fix this as there's code in
+    -- xmonad-contrib that touches the windowset during handleMessage
+    -- (returning Nothing for changes to not get overwritten), so we
+    -- unfortunately need to do this one by one and persist layout states
+    -- of each workspace separately)
+    let c = W.workspace . W.current $ ws
+        v = map W.workspace . W.visible $ ws
+        h = W.hidden ws
+    mapM_ (sendMessageWithNoRefresh a) (c : v ++ h)
 
 -- | Send a message to a layout, without refreshing.
-sendMessageWithNoRefresh :: Message a => a -> W.Workspace WorkspaceId (Layout Window) Window -> X ()
+sendMessageWithNoRefresh :: Message a => a -> WindowSpace -> X ()
 sendMessageWithNoRefresh a w =
     handleMessage (W.layout w) (SomeMessage a) `catchX` return Nothing >>=
     updateLayout  (W.tag w)
 
--- | Update the layout field of a workspace
+-- | Update the layout field of a workspace.
 updateLayout :: WorkspaceId -> Maybe (Layout Window) -> X ()
 updateLayout i ml = whenJust ml $ \l ->
     runOnWorkspaces $ \ww -> return $ if W.tag ww == i then ww { W.layout = l} else ww
 
--- | Set the layout of the currently viewed workspace
+-- | Set the layout of the currently viewed workspace.
 setLayout :: Layout Window -> X ()
 setLayout l = do
-    ss@(W.StackSet { W.current = c@(W.Screen { W.workspace = ws })}) <- gets windowset
+    ss@W.StackSet{ W.current = c@W.Screen{ W.workspace = ws }} <- gets windowset
     handleMessage (W.layout ws) (SomeMessage ReleaseResources)
-    windows $ const $ ss {W.current = c { W.workspace = ws { W.layout = l } } }
+    windows $ const $ ss{ W.current = c{ W.workspace = ws{ W.layout = l } } }
+
+-- | Signal xmonad to restart itself.
+sendRestart :: IO ()
+sendRestart = do
+    dpy <- openDisplay ""
+    rw  <- rootWindow dpy $ defaultScreen dpy
+    xmonad_restart <- internAtom dpy "XMONAD_RESTART" False
+    allocaXEvent $ \e -> do
+        setEventType e clientMessage
+        setClientMessageEvent' e rw xmonad_restart 32 []
+        sendEvent dpy rw False structureNotifyMask e
+    sync dpy False
+
+-- | Signal compliant window managers to exit.
+sendReplace :: IO ()
+sendReplace = do
+    dpy <- openDisplay ""
+    let dflt = defaultScreen dpy
+    rootw <- rootWindow dpy dflt
+    replace dpy dflt rootw
+
+-- | Signal compliant window managers to exit.
+replace :: Display -> ScreenNumber -> Window -> IO ()
+replace dpy dflt rootw = do
+    -- check for other WM
+    wmSnAtom <- internAtom dpy ("WM_S" ++ show dflt) False
+    currentWmSnOwner <- xGetSelectionOwner dpy wmSnAtom
+    when (currentWmSnOwner /= 0) $ do
+        -- prepare to receive destroyNotify for old WM
+        selectInput dpy currentWmSnOwner structureNotifyMask
+
+        -- create off-screen window
+        netWmSnOwner <- allocaSetWindowAttributes $ \attributes -> do
+            set_override_redirect attributes True
+            set_event_mask attributes propertyChangeMask
+            let screen = defaultScreenOfDisplay dpy
+                visual = defaultVisualOfScreen screen
+                attrmask = cWOverrideRedirect .|. cWEventMask
+            createWindow dpy rootw (-100) (-100) 1 1 0 copyFromParent copyFromParent visual attrmask attributes
+
+        -- try to acquire wmSnAtom, this should signal the old WM to terminate
+        xSetSelectionOwner dpy wmSnAtom netWmSnOwner currentTime
+
+        -- SKIPPED: check if we acquired the selection
+        -- SKIPPED: send client message indicating that we are now the WM
+
+        -- wait for old WM to go away
+        fix $ \again -> do
+            evt <- allocaXEvent $ \event -> do
+                windowEvent dpy currentWmSnOwner structureNotifyMask event
+                get_EventType event
+
+            when (evt /= destroyNotify) again
 
 ------------------------------------------------------------------------
 -- Utilities
 
--- | Return workspace visible on screen 'sc', or 'Nothing'.
+-- | Return workspace visible on screen @sc@, or 'Nothing'.
 screenWorkspace :: ScreenId -> X (Maybe WorkspaceId)
 screenWorkspace sc = withWindowSet $ return . W.lookupWorkspace sc
 
@@ -418,7 +607,14 @@ screenWorkspace sc = withWindowSet $ return . W.lookupWorkspace sc
 withFocused :: (Window -> X ()) -> X ()
 withFocused f = withWindowSet $ \w -> whenJust (W.peek w) f
 
--- | 'True' if window is under management by us
+-- | Apply an 'X' operation to all unfocused windows on the current workspace, if there are any.
+withUnfocused :: (Window -> X ()) -> X ()
+withUnfocused f = withWindowSet $ \ws ->
+    whenJust (W.peek ws) $ \w ->
+        let unfocusedWindows = filter (/= w) $ W.index ws
+        in mapM_ f unfocusedWindows
+
+-- | Is the window is under management by xmonad?
 isClient :: Window -> X Bool
 isClient w = withWindowSet $ return . W.member w
 
@@ -429,16 +625,20 @@ extraModifiers = do
     nlm <- gets numberlockMask
     return [0, nlm, lockMask, nlm .|. lockMask ]
 
--- | Strip numlock\/capslock from a mask
+-- | Strip numlock\/capslock from a mask.
 cleanMask :: KeyMask -> X KeyMask
 cleanMask km = do
     nlm <- gets numberlockMask
     return (complement (nlm .|. lockMask) .&. km)
 
--- | Get the 'Pixel' value for a named color
+-- | Set the 'Pixel' alpha value to 255.
+setPixelSolid :: Pixel -> Pixel
+setPixelSolid p = p .|. 0xff000000
+
+-- | Get the 'Pixel' value for a named color.
 initColor :: Display -> String -> IO (Maybe Pixel)
 initColor dpy c = C.handle (\(C.SomeException _) -> return Nothing) $
-    (Just . color_pixel . fst) <$> allocNamedColor dpy colormap c
+    Just . setPixelSolid . color_pixel . fst <$> allocNamedColor dpy colormap c
     where colormap = defaultColormap dpy (defaultScreen dpy)
 
 ------------------------------------------------------------------------
@@ -458,9 +658,9 @@ writeStateToFile = do
         maybeShow _ = Nothing
 
         wsData   = W.mapLayout show . windowset
-        extState = catMaybes . map maybeShow . M.toList . extensibleState
+        extState = mapMaybe maybeShow . M.toList . extensibleState
 
-    path  <- stateFileName
+    path <- asks $ stateFileName . directories
     stateData <- gets (\s -> StateFile (wsData s) (extState s))
     catchIO (writeFile path $ show stateData)
 
@@ -468,7 +668,7 @@ writeStateToFile = do
 -- return that state.  The state file is removed after reading it.
 readStateFile :: (LayoutClass l Window, Read (l Window)) => XConfig l -> X (Maybe XState)
 readStateFile xmc = do
-    path <- stateFileName
+    path <- asks $ stateFileName . directories
 
     -- I'm trying really hard here to make sure we read the entire
     -- contents of the file before it is removed from the file system.
@@ -501,23 +701,8 @@ readStateFile xmc = do
     readStrict :: Handle -> IO String
     readStrict h = hGetContents h >>= \s -> length s `seq` return s
 
--- | Migrate state from a previously running xmonad instance that used
--- the older @--resume@ technique.
-{-# DEPRECATED migrateState "will be removed some point in the future." #-}
-migrateState :: (Functor m, MonadIO m) => String -> String -> m ()
-migrateState ws xs = do
-    io (putStrLn "WARNING: --resume is no longer supported.")
-    whenJust stateData $ \s -> do
-      path <- stateFileName
-      catchIO (writeFile path $ show s)
-  where
-    stateData = StateFile <$> maybeRead ws <*> maybeRead xs
-    maybeRead s = case reads s of
-                    [(x, "")] -> Just x
-                    _         -> Nothing
-
--- | @restart name resume@. Attempt to restart xmonad by executing the program
--- @name@.  If @resume@ is 'True', restart with the current window state.
+-- | @restart name resume@ attempts to restart xmonad by executing the program
+-- @name@. If @resume@ is 'True', restart with the current window state.
 -- When executing another window manager, @resume@ should be 'False'.
 restart :: String -> Bool -> X ()
 restart prog resume = do
@@ -527,33 +712,49 @@ restart prog resume = do
     catchIO (executeFile prog True [] Nothing)
 
 ------------------------------------------------------------------------
--- | Floating layer support
+-- Floating layer support
 
 -- | Given a window, find the screen it is located on, and compute
--- the geometry of that window wrt. that screen.
+-- the geometry of that window WRT that screen.
 floatLocation :: Window -> X (ScreenId, W.RationalRect)
 floatLocation w =
     catchX go $ do
       -- Fallback solution if `go' fails.  Which it might, since it
       -- calls `getWindowAttributes'.
-      sc <- W.current <$> gets windowset
+      sc <- gets $ W.current . windowset
       return (W.screen sc, W.RationalRect 0 0 1 1)
 
-  where fi x = fromIntegral x
-        go = withDisplay $ \d -> do
+  where go = withDisplay $ \d -> do
           ws <- gets windowset
+          sh <- io $ getWMNormalHints d w
           wa <- io $ getWindowAttributes d w
           let bw = (fromIntegral . wa_border_width) wa
-          sc <- fromMaybe (W.current ws) <$> pointScreen (fi $ wa_x wa) (fi $ wa_y wa)
+          point_sc <- pointScreen (fi $ wa_x wa) (fi $ wa_y wa)
+          managed <- isClient w
 
-          let sr = screenRect . W.screenDetail $ sc
-              rr = W.RationalRect ((fi (wa_x wa) - fi (rect_x sr)) % fi (rect_width sr))
-                                  ((fi (wa_y wa) - fi (rect_y sr)) % fi (rect_height sr))
-                                  (fi (wa_width  wa + bw*2) % fi (rect_width sr))
-                                  (fi (wa_height wa + bw*2) % fi (rect_height sr))
+          -- ignore pointScreen for new windows unless it's the current
+          -- screen, otherwise the float's relative size is computed against
+          -- a different screen and the float ends up with the wrong size
+          let sr_eq = (==) `on` fmap (screenRect . W.screenDetail)
+              sc = fromMaybe (W.current ws) $
+                  if managed || point_sc `sr_eq` Just (W.current ws) then point_sc else Nothing
+              sr = screenRect . W.screenDetail $ sc
+              x = (fi (wa_x wa) - fi (rect_x sr)) % fi (rect_width sr)
+              y = (fi (wa_y wa) - fi (rect_y sr)) % fi (rect_height sr)
+              (width, height) = applySizeHintsContents sh (wa_width wa, wa_height wa)
+              rwidth  = fi (width + bw*2) % fi (rect_width sr)
+              rheight = fi (height + bw*2) % fi (rect_height sr)
+              -- adjust x/y of unmanaged windows if we ignored or didn't get pointScreen,
+              -- it might be out of bounds otherwise
+              rr = if managed || point_sc `sr_eq` Just sc
+                  then W.RationalRect x y rwidth rheight
+                  else W.RationalRect (0.5 - rwidth/2) (0.5 - rheight/2) rwidth rheight
 
           return (W.screen sc, rr)
 
+        fi :: (Integral a, Num b) => a -> b
+        fi = fromIntegral
+
 -- | Given a point, determine the screen (if any) that contains it.
 pointScreen :: Position -> Position
             -> X (Maybe (W.Screen WorkspaceId (Layout Window) Window ScreenId ScreenDetail))
@@ -584,14 +785,20 @@ float w = do
 
 -- | Accumulate mouse motion events
 mouseDrag :: (Position -> Position -> X ()) -> X () -> X ()
-mouseDrag f done = do
+mouseDrag = mouseDragCursor Nothing
+
+-- | Like 'mouseDrag', but with the ability to specify a custom cursor
+-- shape.
+mouseDragCursor :: Maybe Glyph -> (Position -> Position -> X ()) -> X () -> X ()
+mouseDragCursor cursorGlyph f done = do
     drag <- gets dragging
     case drag of
         Just _ -> return () -- error case? we're already dragging
         Nothing -> do
             XConf { theRoot = root, display = d } <- ask
-            io $ grabPointer d root False (buttonReleaseMask .|. pointerMotionMask)
-                    grabModeAsync grabModeAsync none none currentTime
+            io $ do cursor <- maybe (pure none) (createFontCursor d) cursorGlyph
+                    grabPointer d root False (buttonReleaseMask .|. pointerMotionMask)
+                      grabModeAsync grabModeAsync none cursor currentTime
             modify $ \s -> s { dragging = Just (motion, cleanup) }
  where
     cleanup = do
@@ -602,39 +809,41 @@ mouseDrag f done = do
                     clearEvents pointerMotionMask
                     return z
 
--- | drag the window under the cursor with the mouse while it is dragged
+-- | Drag the window under the cursor with the mouse while it is dragged.
 mouseMoveWindow :: Window -> X ()
 mouseMoveWindow w = whenX (isClient w) $ withDisplay $ \d -> do
-    io $ raiseWindow d w
     wa <- io $ getWindowAttributes d w
     (_, _, _, ox', oy', _, _, _) <- io $ queryPointer d w
     let ox = fromIntegral ox'
         oy = fromIntegral oy'
-    mouseDrag (\ex ey -> do
+    mouseDragCursor
+              (Just xC_fleur)
+              (\ex ey -> do
                   io $ moveWindow d w (fromIntegral (fromIntegral (wa_x wa) + (ex - ox)))
                                       (fromIntegral (fromIntegral (wa_y wa) + (ey - oy)))
                   float w
               )
               (float w)
 
--- | resize the window under the cursor with the mouse while it is dragged
+-- | Resize the window under the cursor with the mouse while it is dragged.
 mouseResizeWindow :: Window -> X ()
 mouseResizeWindow w = whenX (isClient w) $ withDisplay $ \d -> do
-    io $ raiseWindow d w
     wa <- io $ getWindowAttributes d w
     sh <- io $ getWMNormalHints d w
     io $ warpPointer d none w 0 0 0 0 (fromIntegral (wa_width wa)) (fromIntegral (wa_height wa))
-    mouseDrag (\ex ey -> do
+    mouseDragCursor
+              (Just xC_bottom_right_corner)
+              (\ex ey -> do
                  io $ resizeWindow d w `uncurry`
                     applySizeHintsContents sh (ex - fromIntegral (wa_x wa),
                                                ey - fromIntegral (wa_y wa))
                  float w)
-
               (float w)
 
 -- ---------------------------------------------------------------------
--- | Support for window size hints
+-- Support for window size hints
 
+-- | An alias for a (width, height) pair
 type D = (Dimension, Dimension)
 
 -- | Given a window, build an adjuster function that will reduce the given
@@ -644,7 +853,7 @@ mkAdjust w = withDisplay $ \d -> liftIO $ do
     sh <- getWMNormalHints d w
     wa <- C.try $ getWindowAttributes d w
     case wa of
-         Left  err -> const (return id) (err :: C.SomeException)
+         Left (_ :: C.SomeException) -> return id
          Right wa' ->
             let bw = fromIntegral $ wa_border_width wa'
             in  return $ applySizeHints bw sh
@@ -662,7 +871,7 @@ applySizeHintsContents :: Integral a => SizeHints -> (a, a) -> D
 applySizeHintsContents sh (w, h) =
     applySizeHints' sh (fromIntegral $ max 1 w, fromIntegral $ max 1 h)
 
--- | XXX comment me
+-- | Use X11 size hints to scale a pair of dimensions.
 applySizeHints' :: SizeHints -> D -> D
 applySizeHints' sh =
       maybe id applyMaxSizeHint                   (sh_max_size   sh)

src/XMonad/StackSet.hs

@@ -1,4 +1,5 @@
 {-# LANGUAGE PatternGuards #-}
+{-# LANGUAGE DeriveFunctor #-}
 
 -----------------------------------------------------------------------------
 -- |
@@ -52,9 +53,13 @@ module XMonad.StackSet (
     ) where
 
 import Prelude hiding (filter)
+import Control.Applicative.Backwards (Backwards (Backwards, forwards))
+import Data.Foldable (foldr, toList)
 import Data.Maybe   (listToMaybe,isJust,fromMaybe)
 import qualified Data.List as L (deleteBy,find,splitAt,filter,nub)
 import Data.List ( (\\) )
+import qualified Data.List.NonEmpty as NE
+import Data.List.NonEmpty (NonEmpty((:|)))
 import qualified Data.Map  as M (Map,insert,delete,empty)
 
 -- $intro
@@ -85,25 +90,27 @@ import qualified Data.Map  as M (Map,insert,delete,empty)
 --    continuation reified as a data structure.
 --
 --    The Zipper lets us replace an item deep in a complex data
---    structure, e.g., a tree or a term, without an  mutation.  The
+--    structure, e.g., a tree or a term, without a mutation.  The
 --    resulting data structure will share as much of its components with
 --    the old structure as possible.
 --
---      Oleg Kiselyov, 27 Apr 2005, haskell\@, "Zipper as a delimited continuation"
+--      <https://mail.haskell.org/pipermail/haskell/2005-April/015769.html Oleg Kiselyov, 27 Apr 2005, haskell\@, "Zipper as a delimited continuation">
 --
 -- We use the zipper to keep track of the focused workspace and the
 -- focused window on each workspace, allowing us to have correct focus
 -- by construction. We closely follow Huet's original implementation:
 --
---      G. Huet, /Functional Pearl: The Zipper/,
---      1997, J. Functional Programming 75(5):549-554.
--- and:
---      R. Hinze and J. Jeuring, /Functional Pearl: The Web/.
+--      <https://www.st.cs.uni-saarland.de/edu/seminare/2005/advanced-fp/docs/huet-zipper.pdf G. Huet, Functional Pearl: The Zipper; 1997, J. Functional Programming 75(5):549–554>
 --
--- and Conor McBride's zipper differentiation paper.
--- Another good reference is:
+-- and
 --
---      The Zipper, Haskell wikibook
+--      <https://dspace.library.uu.nl/handle/1874/2532 R. Hinze and J. Jeuring, Functional Pearl: Weaving a Web>
+--
+-- and
+--
+--      <http://strictlypositive.org/diff.pdf Conor McBride, The Derivative of a Regular Type is its Type of One-Hole Contexts>.
+--
+-- Another good reference is: <https://wiki.haskell.org/Zipper The Zipper, Haskell wikibook>
 
 -- $xinerama
 -- Xinerama in X11 lets us view multiple virtual workspaces
@@ -151,7 +158,7 @@ data Workspace i l a = Workspace  { tag :: !i, layout :: l, stack :: Maybe (Stac
     deriving (Show, Read, Eq)
 
 -- | A structure for window geometries
-data RationalRect = RationalRect Rational Rational Rational Rational
+data RationalRect = RationalRect !Rational !Rational !Rational !Rational
     deriving (Show, Read, Eq)
 
 -- |
@@ -175,8 +182,19 @@ data RationalRect = RationalRect Rational Rational Rational Rational
 data Stack a = Stack { focus  :: !a        -- focused thing in this set
                      , up     :: [a]       -- clowns to the left
                      , down   :: [a] }     -- jokers to the right
-    deriving (Show, Read, Eq)
+    deriving (Show, Read, Eq, Functor)
 
+instance Foldable Stack where
+    toList = integrate
+    foldr f z = foldr f z . toList
+
+instance Traversable Stack where
+    traverse f s =
+        flip Stack
+            -- 'Backwards' applies the Applicative in reverse order.
+            <$> forwards (traverse (Backwards . f) (up s))
+            <*> f (focus s)
+            <*> traverse f (down s)
 
 -- | this function indicates to catch that an error is expected
 abort :: String -> a
@@ -194,10 +212,11 @@ abort x = error $ "xmonad: StackSet: " ++ x
 -- Xinerama: Virtual workspaces are assigned to physical screens, starting at 0.
 --
 new :: (Integral s) => l -> [i] -> [sd] -> StackSet i l a s sd
-new l wids m | not (null wids) && length m <= length wids && not (null m)
-  = StackSet cur visi unseen M.empty
-  where (seen,unseen) = L.splitAt (length m) $ map (\i -> Workspace i l Nothing) wids
-        (cur:visi)    = [ Screen i s sd |  (i, s, sd) <- zip3 seen [0..] m ]
+new l (wid:wids) (m:ms) | length ms <= length wids
+  = StackSet cur visi (map ws unseen) M.empty
+  where ws i = Workspace i l Nothing
+        (seen, unseen) = L.splitAt (length ms) wids
+        cur:visi = Screen (ws wid) 0 m : [ Screen (ws i) s sd | (i, s, sd) <- zip3 seen [1..] ms ]
                 -- now zip up visibles with their screen id
 new _ _ _ = abort "non-positive argument to StackSet.new"
 
@@ -224,7 +243,7 @@ view i s
 
     | otherwise = s -- not a member of the stackset
 
-  where equating f = \x y -> f x == f y
+  where equating f x y = f x == f y
 
     -- 'Catch'ing this might be hard. Relies on monotonically increasing
     -- workspace tags defined in 'new'
@@ -297,7 +316,7 @@ integrate :: Stack a -> [a]
 integrate (Stack x l r) = reverse l ++ x : r
 
 -- |
--- /O(n)/ Flatten a possibly empty stack into a list.
+-- /O(n)/. Flatten a possibly empty stack into a list.
 integrate' :: Maybe (Stack a) -> [a]
 integrate' = maybe [] integrate
 
@@ -329,32 +348,44 @@ filter p (Stack f ls rs) = case L.filter p (f:rs) of
 index :: StackSet i l a s sd -> [a]
 index = with [] integrate
 
--- |
--- /O(1), O(w) on the wrapping case/.
---
--- focusUp, focusDown. Move the window focus up or down the stack,
--- wrapping if we reach the end. The wrapping should model a 'cycle'
--- on the current stack. The 'master' window, and window order,
+-- | /O(1), O(w) on the wrapping case/. Move the window focus up the
+-- stack, wrapping if we reach the end. The wrapping should model a
+-- @cycle@ on the current stack. The @master@ window and window order
 -- are unaffected by movement of focus.
---
--- swapUp, swapDown, swap the neighbour in the stack ordering, wrapping
--- if we reach the end. Again the wrapping model should 'cycle' on
--- the current stack.
---
-focusUp, focusDown, swapUp, swapDown :: StackSet i l a s sd -> StackSet i l a s sd
+focusUp :: StackSet i l a s sd -> StackSet i l a s sd
 focusUp   = modify' focusUp'
+
+-- | /O(1), O(w) on the wrapping case/. Like 'focusUp', but move the
+-- window focus down the stack.
+focusDown :: StackSet i l a s sd -> StackSet i l a s sd
 focusDown = modify' focusDown'
 
+-- | /O(1), O(w) on the wrapping case/. Swap the upwards (left)
+-- neighbour in the stack ordering, wrapping if we reach the end. Much
+-- like for 'focusUp' and 'focusDown', the wrapping model should 'cycle'
+-- on the current stack.
+swapUp :: StackSet i l a s sd -> StackSet i l a s sd
 swapUp    = modify' swapUp'
+
+-- | /O(1), O(w) on the wrapping case/. Like 'swapUp', but for swapping
+-- the downwards (right) neighbour.
+swapDown :: StackSet i l a s sd -> StackSet i l a s sd
 swapDown  = modify' (reverseStack . swapUp' . reverseStack)
 
--- | Variants of 'focusUp' and 'focusDown' that work on a
+-- | A variant of 'focusUp' with the same asymptotics that works on a
 -- 'Stack' rather than an entire 'StackSet'.
-focusUp', focusDown' :: Stack a -> Stack a
+focusUp' :: Stack a -> Stack a
 focusUp' (Stack t (l:ls) rs) = Stack l ls (t:rs)
-focusUp' (Stack t []     rs) = Stack x xs [] where (x:xs) = reverse (t:rs)
-focusDown'                   = reverseStack . focusUp' . reverseStack
+focusUp' (Stack t []     rs) = Stack x xs []
+  where (x :| xs) = NE.reverse (t :| rs)
 
+-- | A variant of 'focusDown' with the same asymptotics that works on a
+-- 'Stack' rather than an entire 'StackSet'.
+focusDown' :: Stack a -> Stack a
+focusDown' = reverseStack . focusUp' . reverseStack
+
+-- | A variant of 'spawUp' with the same asymptotics that works on a
+-- 'Stack' rather than an entire 'StackSet'.
 swapUp' :: Stack a -> Stack a
 swapUp'  (Stack t (l:ls) rs) = Stack t ls (l:rs)
 swapUp'  (Stack t []     rs) = Stack t (reverse rs) []
@@ -508,8 +539,8 @@ sink w s = s { floating = M.delete w (floating s) }
 -- Focus stays with the item moved.
 swapMaster :: StackSet i l a s sd -> StackSet i l a s sd
 swapMaster = modify' $ \c -> case c of
-    Stack _ [] _  -> c    -- already master.
-    Stack t ls rs -> Stack t [] (xs ++ x : rs) where (x:xs) = reverse ls
+    Stack _ []     _  -> c    -- already master.
+    Stack t (l:ls) rs -> Stack t [] (xs ++ x : rs) where (x :| xs) = NE.reverse (l :| ls)
 
 -- natural! keep focus, move current to the top, move top to current.
 
@@ -525,8 +556,8 @@ shiftMaster = modify' $ \c -> case c of
 -- | /O(s)/. Set focus to the master window.
 focusMaster :: StackSet i l a s sd -> StackSet i l a s sd
 focusMaster = modify' $ \c -> case c of
-    Stack _ [] _  -> c
-    Stack t ls rs -> Stack x [] (xs ++ t : rs) where (x:xs) = reverse ls
+    Stack _ []     _  -> c
+    Stack t (l:ls) rs -> Stack x [] (xs ++ t : rs) where (x :| xs) = NE.reverse (l :| ls)
 
 --
 -- ---------------------------------------------------------------------

stack.yaml

@@ -1,7 +1,15 @@
-resolver: lts-7.19
+resolver: lts-21.12
 
 packages:
-  - ./
+- ./
 
 extra-deps:
-  - X11-1.8
+- X11-1.10
+
+nix:
+  packages:
+    - zlib
+    - xorg.libX11
+    - xorg.libXrandr
+    - xorg.libXScrnSaver
+    - xorg.libXext

tests/Instances.hs

@@ -36,7 +36,7 @@ instance (Integral i, Integral s, Eq a, Arbitrary a, Arbitrary l, Arbitrary sd)
       -- Pick a random window "number" in each workspace, to give focus.
       focus <- sequence [ if null windows
                           then return Nothing
-                          else liftM Just $ choose (0, length windows - 1)
+                          else Just <$> choose (0, length windows - 1)
                         | windows <- wsWindows ]
 
       let tags = [1 .. fromIntegral numWs]
@@ -80,7 +80,7 @@ newtype NonEmptyWindowsStackSet = NonEmptyWindowsStackSet T
 
 instance Arbitrary NonEmptyWindowsStackSet where
   arbitrary =
-    NonEmptyWindowsStackSet `fmap` (arbitrary `suchThat` (not . null . allWindows))
+    NonEmptyWindowsStackSet <$> (arbitrary `suchThat` (not . null . allWindows))
 
 instance Arbitrary Rectangle where
     arbitrary = Rectangle <$> arbitrary <*> arbitrary <*> arbitrary <*> arbitrary
@@ -99,7 +99,7 @@ newtype NonEmptyNubList a = NonEmptyNubList [a]
     deriving ( Eq, Ord, Show, Read )
 
 instance (Eq a, Arbitrary a) => Arbitrary (NonEmptyNubList a) where
-  arbitrary   = NonEmptyNubList `fmap` ((liftM nub arbitrary) `suchThat` (not . null))
+  arbitrary = NonEmptyNubList <$> ((nub <$> arbitrary) `suchThat` (not . null))
 
 
 
@@ -116,7 +116,7 @@ arbitraryTag :: T -> Gen Tag
 arbitraryTag x = do
   let ts = tags x
   -- There must be at least 1 workspace, thus at least 1 tag.
-  idx <- choose (0, (length ts) - 1)
+  idx <- choose (0, length ts - 1)
   return $ ts!!idx
 
 -- | Pull out an arbitrary window from a StackSet that is guaranteed to have a
@@ -136,5 +136,5 @@ arbitraryWindow :: NonEmptyWindowsStackSet -> Gen Window
 arbitraryWindow (NonEmptyWindowsStackSet x) = do
   let ws = allWindows x
   -- We know that there are at least 1 window in a NonEmptyWindowsStackSet.
-  idx <- choose(0, (length ws) - 1)
+  idx <- choose (0, length ws - 1)
   return $ ws!!idx

tests/Properties.hs

@@ -1,6 +1,6 @@
 import Test.QuickCheck
 
--- Our QC instances and properties.
+-- Our QC instances and properties:
 import Instances
 import Properties.Delete
 import Properties.Failure
@@ -166,11 +166,16 @@ tests =
   -- tall layout
 
   ,("tile 1 window fullsize", property prop_tile_fullscreen)
+  ,("tile max ratio",         property prop_tile_max_ratio)
+  ,("tile min ratio",         property prop_tile_min_ratio)
   ,("tiles never overlap",    property prop_tile_non_overlap)
   ,("split horizontal",       property prop_split_horizontal)
   ,("split vertical",         property prop_split_vertical)
 
-  ,("pure layout tall",       property prop_purelayout_tall)
+  ,("pure layout tall",            property prop_purelayout_tall)
+    {- Following two test cases should be automatically generated by QuickCheck ideally, but it fails. -}
+  ,("pure layout tall: ratio = 0", property (\n d rect -> prop_purelayout_tall n d 0 rect))
+  ,("pure layout tall: ratio = 1", property (\n d rect -> prop_purelayout_tall n d 1 rect))
   ,("send shrink    tall",    property prop_shrink_tall)
   ,("send expand    tall",    property prop_expand_tall)
   ,("send incmaster tall",    property prop_incmaster_tall)
@@ -196,6 +201,5 @@ tests =
   ,("pointWithin",        property prop_point_within)
   ,("pointWithin mirror", property prop_point_within_mirror)
 
-  ]
-
-
+  ] <>
+  prop_laws_Stack

tests/Properties/Delete.hs

@@ -18,7 +18,7 @@ prop_delete x =
     where _ = x :: T
 
 -- delete is reversible with 'insert'.
--- It is the identiy, except for the 'master', which is reset on insert and delete.
+-- It is the identity, except for the 'master', which is reset on insert and delete.
 --
 prop_delete_insert (x :: T) =
     case peek x of
@@ -64,7 +64,7 @@ prop_delete_focus_not_end = do
        -- last one in the stack.
        `suchThat` \(x' :: T) ->
          let currWins = index x'
-         in length (currWins) >= 2 && peek x' /= Just (last currWins)
+         in length currWins >= 2 && peek x' /= Just (last currWins)
   -- This is safe, as we know there are >= 2 windows
   let Just n = peek x
   return $ peek (delete n x) == peek (focusDown x)

tests/Properties/Failure.hs

@@ -2,7 +2,7 @@ module Properties.Failure where
 
 import XMonad.StackSet hiding (filter)
 
-import qualified Control.Exception.Extensible as C
+import qualified Control.Exception as C
 import System.IO.Unsafe
 import Data.List (isPrefixOf)
 

tests/Properties/Focus.hs

@@ -32,8 +32,8 @@ prop_focusWindow_master (NonNegative n) (x :: T) =
                    in index (focusWindow (s !! i) x) == index x
 
 -- shifting focus is trivially reversible
-prop_focus_left  (x :: T) = (focusUp  (focusDown x)) == x
-prop_focus_right (x :: T) = (focusDown (focusUp  x)) ==  x
+prop_focus_left  (x :: T) = focusUp  (focusDown x) == x
+prop_focus_right (x :: T) = focusDown (focusUp  x) == x
 
 -- focus master is idempotent
 prop_focusMaster_idem (x :: T) = focusMaster x == focusMaster (focusMaster x)
@@ -47,9 +47,9 @@ prop_focusWindow_works (NonNegative (n :: Int)) (x :: T) =
                    in (focus . fromJust . stack . workspace . current) (focusWindow (s !! i) x) == (s !! i)
 
 -- rotation through the height of a stack gets us back to the start
-prop_focus_all_l (x :: T) = (foldr (const focusUp) x [1..n]) == x
+prop_focus_all_l (x :: T) = foldr (const focusUp) x [1..n] == x
   where n = length (index x)
-prop_focus_all_r (x :: T) = (foldr (const focusDown) x [1..n]) == x
+prop_focus_all_r (x :: T) = foldr (const focusDown) x [1..n] == x
   where n = length (index x)
 
 -- prop_rotate_all (x :: T) = f (f x) == f x

tests/Properties/GreedyView.hs

@@ -35,7 +35,7 @@ prop_greedyView_local  (x :: T) = do
 -- greedyView is idempotent
 prop_greedyView_idem (x :: T) = do
   n <- arbitraryTag x
-  return $ greedyView n (greedyView n x) == (greedyView n x)
+  return $ greedyView n (greedyView n x) == greedyView n x
 
 -- greedyView is reversible, though shuffles the order of hidden/visible
 prop_greedyView_reversible (x :: T) = do

tests/Properties/Insert.hs

@@ -46,7 +46,7 @@ prop_insert_delete x = do
 
 -- inserting n elements increases current stack size by n
 prop_size_insert is (EmptyStackSet x) =
-        size (foldr insertUp x ws ) ==  (length ws)
+        size (foldr insertUp x ws) == length ws
   where
     ws   = nub is
     size = length . index

tests/Properties/Layout/Full.hs

@@ -29,6 +29,6 @@ prop_purelayout_full rect = do
 
 -- what happens when we send an IncMaster message to Full --- Nothing
 prop_sendmsg_full (NonNegative k) =
-         isNothing (Full `pureMessage` (SomeMessage (IncMasterN k)))
+         isNothing (Full `pureMessage` SomeMessage (IncMasterN k))
 
 prop_desc_full = description Full == show Full

tests/Properties/Layout/Tall.hs

@@ -11,8 +11,9 @@ import XMonad.Layout
 
 import Graphics.X11.Xlib.Types (Rectangle(..))
 
-import Data.Maybe
+import Control.Applicative
 import Data.List (sort)
+import Data.Maybe
 import Data.Ratio
 
 ------------------------------------------------------------------------
@@ -27,14 +28,30 @@ prop_tile_non_overlap rect windows nmaster = noOverlaps (tile pct rect nmaster w
   where _ = rect :: Rectangle
         pct = 3 % 100
 
+-- with a ratio of 1, no stack windows are drawn of there is at least
+-- one master window around.
+prop_tile_max_ratio = extremeRatio 1 drop
+
+-- with a ratio of 0, no master windows are drawn at all if there are
+-- any stack windows around.
+prop_tile_min_ratio = extremeRatio 0 take
+
+extremeRatio amount getRects rect = do
+    w@(NonNegative windows) <- arbitrary `suchThat` (> NonNegative 0)
+    NonNegative nmaster     <- arbitrary `suchThat` (< w)
+    let tiled = tile amount rect nmaster windows
+    pure $ if   nmaster == 0
+           then prop_tile_non_overlap rect windows nmaster
+           else all ((== 0) . rect_width) $ getRects nmaster tiled
+
 -- splitting horizontally yields sensible results
 prop_split_horizontal (NonNegative n) x =
-      (noOverflows (+) (rect_x x) (rect_width x)) ==>
+      noOverflows (+) (rect_x x) (rect_width x) ==>
         sum (map rect_width xs) == rect_width x
      &&
-        all (== rect_height x) (map rect_height xs)
+        all (\s -> rect_height s == rect_height x) xs
      &&
-        (map rect_x xs) == (sort $ map rect_x xs)
+        map rect_x xs == sort (map rect_x xs)
 
     where
         xs = splitHorizontally n x
@@ -49,13 +66,20 @@ prop_split_vertical (r :: Rational) x =
 
 
 -- pureLayout works.
-prop_purelayout_tall n r1 r2 rect = do
+prop_purelayout_tall n d r rect = do
   x <- (arbitrary :: Gen T) `suchThat` (isJust . peek)
-  let layout = Tall n r1 r2
+  let layout = Tall n d r
       st = fromJust . stack . workspace . current $ x
       ts = pureLayout layout rect st
+      ntotal = length (index x)
   return $
-        length ts == length (index x)
+       (if r == 0 then
+          -- (<=) for Bool is the logical implication
+          (0 <= n && n <= ntotal) <= (length ts == ntotal - n)
+        else if r == 1 then
+          (0 <= n && n <= ntotal) <= (length ts == n)
+        else
+          length ts == ntotal)
       &&
         noOverlaps (map snd ts)
       &&
@@ -72,7 +96,7 @@ prop_shrink_tall (NonNegative n) (Positive delta) (NonNegative frac) =
         -- remaining fraction should shrink
     where
          l1                   = Tall n delta frac
-         Just l2@(Tall n' delta' frac') = l1 `pureMessage` (SomeMessage Shrink)
+         Just l2@(Tall n' delta' frac') = l1 `pureMessage` SomeMessage Shrink
         --  pureMessage :: layout a -> SomeMessage -> Maybe (layout a)
 
 
@@ -93,7 +117,7 @@ prop_expand_tall (NonNegative n)
     where
          frac                 = min 1 (n1 % d1)
          l1                   = Tall n delta frac
-         Just l2@(Tall n' delta' frac') = l1 `pureMessage` (SomeMessage Expand)
+         Just l2@(Tall n' delta' frac') = l1 `pureMessage` SomeMessage Expand
         --  pureMessage :: layout a -> SomeMessage -> Maybe (layout a)
 
 -- what happens when we send an IncMaster message to Tall
@@ -102,7 +126,7 @@ prop_incmaster_tall (NonNegative n) (Positive delta) (NonNegative frac)
        delta == delta'  && frac == frac' && n' == n + k
     where
          l1                   = Tall n delta frac
-         Just l2@(Tall n' delta' frac') = l1 `pureMessage` (SomeMessage (IncMasterN k))
+         Just l2@(Tall n' delta' frac') = l1 `pureMessage` SomeMessage (IncMasterN k)
         --  pureMessage :: layout a -> SomeMessage -> Maybe (layout a)
 
 

tests/Properties/Screen.hs

@@ -52,15 +52,14 @@ prop_aspect_hint_shrink hint (w,h) = case applyAspectHint hint (w,h) of
 -- applyAspectHint does nothing when the supplied (x,y) fits
 -- the desired range
 prop_aspect_fits =
-    forAll ((,,,) <$> pos <*> pos <*> pos <*> pos) $ \ (x,y,a,b) -> 
-    let f v = applyAspectHint ((x, y+a), (x+b, y)) v
-    in  and [ noOverflows (*) x (y+a), noOverflows (*) (x+b) y ]
+    forAll ((,,,) <$> pos <*> pos <*> pos <*> pos) $ \ (x,y,a,b) ->
+    let f = applyAspectHint ((x, y+a), (x+b, y))
+    in  noOverflows (*) x (y+a) && noOverflows (*) (x+b) y
             ==> f (x,y) == (x,y)
 
   where pos = choose (0, 65535)
-        mul a b = toInteger (a*b) /= toInteger a * toInteger b
 
-prop_point_within r @ (Rectangle x y w h) =
+prop_point_within r@(Rectangle x y w h) =
     forAll ((,) <$>
               choose (0, fromIntegral w - 1) <*>
               choose (0, fromIntegral h - 1)) $

tests/Properties/Shift.hs

@@ -27,7 +27,7 @@ prop_shift_reversible (x :: T) = do
 -- shiftMaster
 
 -- focus/local/idempotent same as swapMaster:
-prop_shift_master_focus (x :: T) = peek x == (peek $ shiftMaster x)
+prop_shift_master_focus (x :: T) = peek x == peek (shiftMaster x)
 prop_shift_master_local (x :: T) = hidden_spaces x == hidden_spaces (shiftMaster x)
 prop_shift_master_idempotent (x :: T) = shiftMaster (shiftMaster x) == shiftMaster x
 -- ordering is constant modulo the focused window:
@@ -57,14 +57,14 @@ prop_shift_win_fix_current = do
   x <- arbitrary `suchThat` \(x' :: T) ->
          -- Invariant, otherWindows are NOT in the current workspace.
          let otherWindows = allWindows x' L.\\ index x'
-         in  length(tags x') >= 2 && length(otherWindows) >= 1
+         in  length (tags x') >= 2 && not (null otherWindows)
   -- Sadly we have to construct `otherWindows` again, for the actual StackSet
   -- that got chosen.
   let otherWindows = allWindows x L.\\ index x
   -- We know such tag must exists, due to the precondition
   n <- arbitraryTag x `suchThat` (/= currentTag x)
   -- we know length is >= 1, from above precondition
-  idx <- choose(0, length(otherWindows) - 1)
+  idx <- choose (0, length otherWindows - 1)
   let w = otherWindows !! idx
-  return $ (current $ x) == (current $ shiftWin n w x)
+  return $ current x == current (shiftWin n w x)
 

tests/Properties/Stack.hs

@@ -1,4 +1,6 @@
 {-# LANGUAGE ScopedTypeVariables #-}
+{-# LANGUAGE GeneralizedNewtypeDeriving #-}
+
 module Properties.Stack where
 
 import Test.QuickCheck
@@ -9,12 +11,18 @@ import qualified XMonad.StackSet as S (filter)
 
 import Data.Maybe
 
+import Data.Proxy
+import Test.QuickCheck.Classes (
+    Laws (lawsTypeclass, lawsProperties), Proxy1 (Proxy1),
+    foldableLaws, traversableLaws,
+    )
+
 
 -- The list returned by index should be the same length as the actual
 -- windows kept in the zipper
 prop_index_length (x :: T) =
     case stack . workspace . current $ x of
-        Nothing   -> length (index x) == 0
+        Nothing -> null (index x)
         Just it -> length (index x) == length (focus it : up it ++ down it)
 
 
@@ -33,7 +41,7 @@ prop_allWindowsMember (NonEmptyWindowsStackSet x) = do
       -- which is a key component in this test (together with member).
   let ws = allWindows x
   -- We know that there are at least 1 window in a NonEmptyWindowsStackSet.
-  idx <- choose(0, (length ws) - 1)
+  idx <- choose (0, length ws - 1)
   return $ member (ws!!idx) x
 
 
@@ -46,6 +54,24 @@ prop_filter_order (x :: T) =
 -- differentiate should return Nothing if the list is empty or Just stack, with
 -- the first element of the list is current, and the rest of the list is down.
 prop_differentiate xs =
-        if null xs then differentiate xs == Nothing
-                   else (differentiate xs) == Just (Stack (head xs) [] (tail xs))
+        if null xs then isNothing (differentiate xs)
+                   else differentiate xs == Just (Stack (head xs) [] (tail xs))
     where _ = xs :: [Int]
+
+
+-- Check type class laws of 'Data.Foldable.Foldable' and 'Data.Traversable.Traversable'.
+newtype TestStack a = TestStack (Stack a)
+    deriving (Eq, Read, Show, Foldable, Functor)
+
+instance (Arbitrary a) => Arbitrary (TestStack a) where
+   arbitrary = TestStack <$> (Stack <$> arbitrary <*> arbitrary <*> arbitrary)
+   shrink = traverse shrink
+
+instance Traversable TestStack where
+   traverse f (TestStack sx) = fmap TestStack (traverse f sx)
+
+prop_laws_Stack = format (foldableLaws p) <> format (traversableLaws p)
+  where
+    p = Proxy :: Proxy TestStack
+    format laws = [ ("Stack: " <> lawsTypeclass laws <> ": " <> name, prop)
+                  | (name, prop) <- lawsProperties laws ]

tests/Properties/StackSet.hs

@@ -58,7 +58,7 @@ invariant (s :: T) = and
 --  inBounds  = and [ w >=0 && w < size s | (w,sc) <- M.assocs (screens s) ]
 
 monotonic []       = True
-monotonic (x:[])   = True
+monotonic [x]      = True
 monotonic (x:y:zs) | x == y-1  = monotonic (y:zs)
                    | otherwise = False
 
@@ -126,7 +126,7 @@ prop_empty (EmptyStackSet x) =
 prop_empty_current (EmptyStackSet x) = currentTag x == head (tags x)
 
 -- no windows will be a member of an empty workspace
-prop_member_empty i (EmptyStackSet x) = member i x == False
+prop_member_empty i (EmptyStackSet x) = not (member i x)
 
 -- peek either yields nothing on the Empty workspace, or Just a valid window
 prop_member_peek (x :: T) =

tests/Properties/Swap.hs

@@ -11,8 +11,8 @@ import XMonad.StackSet hiding (filter)
 -- swapUp, swapDown, swapMaster: reordiring windows
 
 -- swap is trivially reversible
-prop_swap_left  (x :: T) = (swapUp  (swapDown x)) == x
-prop_swap_right (x :: T) = (swapDown (swapUp  x)) ==  x
+prop_swap_left  (x :: T) = swapUp  (swapDown x) == x
+prop_swap_right (x :: T) = swapDown (swapUp  x) ==  x
 -- TODO swap is reversible
 -- swap is reversible, but involves moving focus back the window with
 -- master on it. easy to do with a mouse...
@@ -26,12 +26,12 @@ prop_promote_reversible x b = (not . null . fromMaybe [] . flip index x . curren
 -}
 
 -- swap doesn't change focus
-prop_swap_master_focus (x :: T) = peek x == (peek $ swapMaster x)
+prop_swap_master_focus (x :: T) = peek x == peek (swapMaster x)
 --    = case peek x of
 --        Nothing -> True
 --        Just f  -> focus (stack (workspace $ current (swap x))) == f
-prop_swap_left_focus   (x :: T) = peek x == (peek $ swapUp   x)
-prop_swap_right_focus  (x :: T) = peek x == (peek $ swapDown  x)
+prop_swap_left_focus   (x :: T) = peek x == peek (swapUp   x)
+prop_swap_right_focus  (x :: T) = peek x == peek (swapDown  x)
 
 -- swap is local
 prop_swap_master_local (x :: T) = hidden_spaces x == hidden_spaces (swapMaster x)
@@ -39,9 +39,9 @@ prop_swap_left_local   (x :: T) = hidden_spaces x == hidden_spaces (swapUp   x)
 prop_swap_right_local  (x :: T) = hidden_spaces x == hidden_spaces (swapDown  x)
 
 -- rotation through the height of a stack gets us back to the start
-prop_swap_all_l (x :: T) = (foldr (const swapUp)  x [1..n]) == x
+prop_swap_all_l (x :: T) = foldr (const swapUp)  x [1..n] == x
   where n = length (index x)
-prop_swap_all_r (x :: T) = (foldr (const swapDown) x [1..n]) == x
+prop_swap_all_r (x :: T) = foldr (const swapDown) x [1..n] == x
   where n = length (index x)
 
 prop_swap_master_idempotent (x :: T) = swapMaster (swapMaster x) == swapMaster x

tests/Properties/View.hs

@@ -37,7 +37,7 @@ prop_view_local  (x :: T) = do
 -- view is idempotent
 prop_view_idem (x :: T) = do
     n <- arbitraryTag x
-    return $ view n (view n x) == (view n x)
+    return $ view n (view n x) == view n x
 
 -- view is reversible, though shuffles the order of hidden/visible
 prop_view_reversible (x :: T) = do

tests/Utils.hs

@@ -12,8 +12,8 @@ hidden_spaces x = map workspace (visible x) ++ hidden x
 -- normalise workspace list
 normal s = s { hidden = sortBy g (hidden s), visible = sortBy f (visible s) }
     where
-        f = \a b -> tag (workspace a) `compare` tag (workspace b)
-        g = \a b -> tag a `compare` tag b
+        f a b = tag (workspace a) `compare` tag (workspace b)
+        g a b = tag a `compare` tag b
 
 
 noOverlaps []  = True

util/GenerateManpage.hs

@@ -1,47 +1,20 @@
-{-# LANGUAGE FlexibleContexts #-}
+#!/usr/bin/env runhaskell
 
--- Generates a in-memory version of "man/xmonad.1.markdown" that has the list
--- of known key-bindings is inserted automatically from "Config.hs". That
--- document is then rendered with Pandoc as "man/xmonad.1" and
--- "man/xmonad.1.html".
+-- Reads markdown (man/xmonad.1.markdown) from stdin, subtitutes
+-- ___KEYBINDINGS___ for key-binding definitions generated from
+-- src/XMonad/Config.hs, prints result to stdout.
 --
 -- Unlike the rest of xmonad, this file is released under the GNU General
--- Public License version 2 or later.
+-- Public License version 2 or later. (Historical reasons, used to link with
+-- GPL-licensed pandoc.)
 
-import Control.Monad.IO.Class (liftIO)
 import Data.Char
 import Data.List
-import qualified Data.Text as T
-import qualified Data.Text.IO as TIO
-import Text.Pandoc
-import Text.Regex.Posix
 
 main :: IO ()
 main = do
     keybindings <- guessBindings
-
-    markdownSource <- readFile "./man/xmonad.1.markdown"
-
-    runIOorExplode $ do
-        parsed <- readMarkdown (def { readerStandalone = True, readerExtensions = pandocExtensions })
-            . T.pack
-            . unlines
-            . replace "___KEYBINDINGS___" keybindings
-            . lines
-            $ markdownSource
-
-        manTemplate <- getDefaultTemplate "man"
-        manBody <- writeMan def { writerTemplate = Just manTemplate } parsed
-        liftIO $ TIO.writeFile "./man/xmonad.1" $ manBody
-        liftIO $ putStrLn "Documentation created: man/xmonad.1"
-
-        htmltemplate <- getDefaultTemplate "html"
-        htmlBody <- writeHtml5String def
-                                     { writerTemplate = Just htmltemplate
-                                     , writerTableOfContents = True }
-                                     parsed
-        liftIO $ TIO.writeFile "./man/xmonad.1.html" htmlBody
-        liftIO $ putStrLn "Documentation created: man/xmonad.1.html"
+    interact $ unlines . replace "___KEYBINDINGS___" keybindings . lines
 
 -- | The format for the docstrings in "Config.hs" takes the following form:
 --
@@ -49,7 +22,7 @@ main = do
 --   -- mod-x %! Frob the whatsit
 -- @
 --
--- "Frob the whatsit" will be used as the description for keybinding "mod-x".--
+-- "Frob the whatsit" will be used as the description for keybinding "mod-x".
 -- If the name of the key binding is omitted, the function tries to guess it
 -- from the rest of the line. For example:
 --
@@ -61,25 +34,33 @@ main = do
 
 guessBindings :: IO String
 guessBindings = do
-  buf <- readFile "./src/XMonad/Config.hs"
-  return (intercalate "\n\n" (map markdownDefn (allBindings buf)))
+    buf <- readFile "./src/XMonad/Config.hs"
+    return (intercalate "\n\n" (map markdownDefn (allBindings buf)))
 
 allBindings :: String -> [(String, String)]
-allBindings xs = map (binding . map trim) (xs =~ "(.*)--(.*)%!(.*)")
-
-binding :: [String] -> (String, String)
-binding [ _, bindingLine, "", desc ] = (guessKeys bindingLine, desc)
-binding [ _, _, keyCombo, desc ] = (keyCombo, desc)
-binding x = error ("binding: called with unexpected argument " ++ show x)
-
-guessKeys :: String -> String
-guessKeys line =
-  case keys of
-    [key] -> concat $ intersperse "-" (modifiers ++ [map toLower key])
-    _     -> error ("guessKeys: unexpected number of keys " ++ show keys)
+allBindings = concatMap parseLine . lines
   where
-    modifiers = map (!!1) (line =~ "(mod|shift|control)Mask")
-    (_, _, _, keys) = line =~ "xK_([_[:alnum:]]+)" :: (String, String, String, [String])
+    parseLine :: String -> [(String, String)]
+    parseLine l
+        | " -- " `isInfixOf` l
+        , Just d <- parseDesc l = [(intercalate "-" (parseKeys l), d)]
+        | otherwise = []
+
+    parseDesc :: String -> Maybe String
+    parseDesc = fmap (trim . drop 4) . find (" %! " `isPrefixOf`) . tails
+
+    parseKeys :: String -> [String]
+    parseKeys l = case lex l of
+        [("", _)] -> []
+        [("--", rest)] -> case words rest of
+            k : "%!" : _ -> [k]
+            _ -> []
+        [(k, rest)] -> parseKey k ++ parseKeys rest
+
+    parseKey :: String -> [String]
+    parseKey k | "Mask" `isSuffixOf` k = [reverse (drop 4 (reverse k))]
+               | "xK_"  `isPrefixOf` k = [map toLower (drop 3 k)]
+               | otherwise             = []
 
 -- FIXME: What escaping should we be doing on these strings?
 markdownDefn :: (String, String) -> String

xmonad.cabal

@@ -1,5 +1,5 @@
 name:               xmonad
-version:            0.14.1
+version:            0.18.0
 synopsis:           A tiling window manager
 description:        xmonad is a tiling window manager for X. Windows are arranged
                     automatically to tile the screen without gaps or overlap, maximising
@@ -12,53 +12,47 @@ description:        xmonad is a tiling window manager for X. Windows are arrange
                     screens.
 license:            BSD3
 license-file:       LICENSE
-author:             Spencer Janssen, Don Stewart, Adam Vogt, David Roundy, Jason Creighton
-                  , Brent Yorgey, Peter Jones, Peter Simons, Andrea Rossato, Devin Mullins
-                  , Lukas Mai, Alec Berryman, Stefan O'Rear, Daniel Wagner, Peter J. Jones
-                  , Daniel Schoepe, Karsten Schoelzel, Neil Mitchell, Joachim Breitner
-                  , Peter De Wachter, Eric Mertens, Geoff Reedy, Michiel Derhaeg
-                  , Philipp Balzarek, Valery V. Vorotyntsev, Alex Tarkovsky, Fabian Beuke
-                  , Felix Hirn, Michael Sloan, Tomas Janousek, Vanessa McHale, Nicolas Pouillard
-                  , Aaron Denney, Austin Seipp, Benno Fünfstück, Brandon S Allbery, Chris Mears
-                  , Christian Thiemann, Clint Adams, Daniel Neri, David Lazar, Ferenc Wagner
-                  , Francesco Ariis, Gábor Lipták, Ivan N. Veselov, Ivan Tarasov, Javran Cheng
-                  , Jens Petersen, Joey Hess, Jonne Ransijn, Josh Holland, Khudyakov Alexey
-                  , Klaus Weidner, Michael G. Sloan, Mikkel Christiansen, Nicolas Dudebout
-                  , Ondřej Súkup, Paul Hebble, Shachaf Ben-Kiki, Siim Põder, Tim McIver
-                  , Trevor Elliott, Wouter Swierstra, Conrad Irwin, Tim Thelion
+author:             Spencer Janssen, Don Stewart, Adam Vogt, David Roundy, Jason Creighton,
+                    Brent Yorgey, Peter Jones, Peter Simons, Andrea Rossato, Devin Mullins,
+                    Lukas Mai, Alec Berryman, Stefan O'Rear, Daniel Wagner, Peter J. Jones,
+                    Daniel Schoepe, Karsten Schoelzel, Neil Mitchell, Joachim Breitner,
+                    Peter De Wachter, Eric Mertens, Geoff Reedy, Michiel Derhaeg,
+                    Philipp Balzarek, Valery V. Vorotyntsev, Alex Tarkovsky, Fabian Beuke,
+                    Felix Hirn, Michael Sloan, Tomas Janousek, Vanessa McHale, Nicolas Pouillard,
+                    Aaron Denney, Austin Seipp, Benno Fünfstück, Brandon S Allbery, Chris Mears,
+                    Christian Thiemann, Clint Adams, Daniel Neri, David Lazar, Ferenc Wagner,
+                    Francesco Ariis, Gábor Lipták, Ivan N. Veselov, Ivan Tarasov, Javran Cheng,
+                    Jens Petersen, Joey Hess, Jonne Ransijn, Josh Holland, Khudyakov Alexey,
+                    Klaus Weidner, Michael G. Sloan, Mikkel Christiansen, Nicolas Dudebout,
+                    Ondřej Súkup, Paul Hebble, Shachaf Ben-Kiki, Siim Põder, Tim McIver,
+                    Trevor Elliott, Wouter Swierstra, Conrad Irwin, Tim Thelion, Tony Zorman
 maintainer:         xmonad@haskell.org
-tested-with:        GHC == 8.0.2, GHC == 8.2.2, GHC == 8.4.3, GHC == 8.6.1
+tested-with:        GHC == 8.6.5 || == 8.8.4 || == 8.10.7 || == 9.0.2 || == 9.2.8 || == 9.4.8 || == 9.6.4 || == 9.8.1
 category:           System
 homepage:           http://xmonad.org
 bug-reports:        https://github.com/xmonad/xmonad/issues
 build-type:         Simple
 extra-source-files: README.md
                     CHANGES.md
-                    CONFIG
-                    STYLE
-                    tests/*.hs
-                    tests/Properties/*.hs
-                    tests/Properties/Layout/*.hs
+                    CONTRIBUTING.md
+                    INSTALL.md
+                    MAINTAINERS.md
+                    TUTORIAL.md
                     man/xmonad.1.markdown
                     man/xmonad.1
                     man/xmonad.1.html
-                    util/GenerateManpage.hs
+                    man/xmonad.hs
                     util/hpcReport.sh
-cabal-version:      >= 1.8
+cabal-version:      1.12
 
 source-repository head
   type:     git
   location: https://github.com/xmonad/xmonad
 
-flag testing
+flag pedantic
+  description: Be pedantic (-Werror and the like)
   default:     False
   manual:      True
-  description: Testing mode, only build minimal components
-
-flag generatemanpage
-  default:     False
-  manual:      True
-  description: Build the tool for generating the man page
 
 library
   exposed-modules: XMonad
@@ -71,36 +65,40 @@ library
                    XMonad.StackSet
   other-modules:   Paths_xmonad
   hs-source-dirs:  src
-  build-depends:   base                  >= 4.9 && < 5
-                 , X11                   >= 1.8 && < 1.10
+  build-depends:   base                  >= 4.11 && < 5
+                 , X11                   >= 1.10 && < 1.11
                  , containers
-                 , data-default
+                 , data-default-class
                  , directory
-                 , extensible-exceptions
                  , filepath
                  , mtl
                  , process
                  , setlocale
+                 , time
+                 , transformers          >= 0.3
                  , unix
-                 , utf8-string           >= 0.3 && < 1.1
-  ghc-options:     -funbox-strict-fields -Wall -fno-warn-unused-do-bind
+  ghc-options:     -funbox-strict-fields -Wall -Wno-unused-do-bind
+  default-language: Haskell2010
 
-  if flag(testing)
-    buildable: False
+  -- Keep this in sync with the oldest version in 'tested-with'
+  if impl(ghc > 8.6.5)
+    ghc-options:   -Wno-unused-imports
+
+  if flag(pedantic)
+    ghc-options:   -Werror
 
 executable xmonad
   main-is:       Main.hs
-  build-depends: base, X11, mtl, unix, xmonad
-  ghc-options:   -Wall -fno-warn-unused-do-bind
+  build-depends: base, xmonad
+  ghc-options:   -Wall -Wno-unused-do-bind
+  default-language: Haskell2010
 
-executable generatemanpage
-  main-is:        GenerateManpage.hs
-  hs-source-dirs: util
+  -- Keep this in sync with the oldest version in 'tested-with'
+  if impl(ghc > 8.6.5)
+    ghc-options:   -Wno-unused-imports
 
-  if flag(generatemanpage)
-    build-depends: base, pandoc >= 2, regex-posix, text
-  else
-    buildable: False
+  if flag(pedantic)
+    ghc-options:   -Werror
 
 test-suite properties
   type:           exitcode-stdio-1.0
@@ -123,4 +121,16 @@ test-suite properties
                   Properties.Workspace
                   Utils
   hs-source-dirs: tests
-  build-depends:  base, QuickCheck >= 2, X11, containers, extensible-exceptions, xmonad
+  build-depends:  base
+                , QuickCheck >= 2
+                , quickcheck-classes >= 0.4.3
+                , X11
+                , containers
+                , xmonad
+  default-language: Haskell2010
+
+  if impl(ghc > 9.8)
+    ghc-options:   -Wno-x-partial
+
+  if flag(pedantic)
+    ghc-options:   -Werror