Merge pull request #532 from xmonad/haskell-ci-update

ci: Regenerate haskell-ci

.github/workflows/generatemanpage.yml

@@ -10,7 +10,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Clone project
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: Install dependencies
         run: |
@@ -26,8 +26,8 @@ jobs:
       - name: Commit/push if changed
         run: |
           set -ex
-          git config user.name github-actions
-          git config user.email github-actions@github.com
+          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

@@ -37,36 +37,43 @@ set in GitHub repository secrets.
  jobs:
    linux:
      name: Haskell-CI - Linux - ${{ matrix.compiler }}
-@@ -31,6 +38,7 @@
-             compilerVersion: 9.0.2
+@@ -33,6 +40,7 @@
+             compilerVersion: 9.8.4
              setup-method: ghcup
              allow-failure: false
 +            upload: true
-           - compiler: ghc-8.10.7
+           - compiler: ghc-9.6.7
              compilerKind: ghc
-             compilerVersion: 8.10.7
-@@ -237,7 +237,7 @@
-           ${CABAL} -vnormal check
+             compilerVersion: 9.6.7
+@@ -257,6 +265,10 @@
        - name: haddock
          run: |
--          $CABAL v2-haddock --disable-documentation $ARG_COMPILER --with-haddock $HADDOCK $ARG_TESTS $ARG_BENCH all
+           $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
-@@ -248,3 +248,75 @@
+@@ -267,3 +279,80 @@
          with:
            key: ${{ runner.os }}-${{ matrix.compiler }}-${{ github.sha }}
            path: ~/.cabal/store
-+      - name: upload artifacts (sdist)
++      # must be separate artifacts because GitHub Actions are still broken:
++      # https://github.com/actions/upload-artifact/issues/441
++      # https://github.com/actions/upload-artifact/issues/457
++      - name: upload artifact (sdist)
 +        if: matrix.upload
-+        uses: actions/upload-artifact@v3
++        uses: actions/upload-artifact@v4
 +        with:
++          name: sdist
 +          path: ${{ github.workspace }}/sdist/*.tar.gz
-+      - name: upload artifacts (haddock)
++      - name: upload artifact (haddock)
 +        if: matrix.upload
-+        uses: actions/upload-artifact@v3
++        uses: actions/upload-artifact@v4
 +        with:
++          name: haddock
 +          path: ${{ github.workspace }}/haddock/*-docs.tar.gz
 +      - name: hackage upload (candidate)
 +        if: matrix.upload && github.event_name == 'workflow_dispatch' && github.event.inputs.version != ''

.github/workflows/haskell-ci.yml

@@ -8,9 +8,9 @@
 #
 # For more information, see https://github.com/haskell-CI/haskell-ci
 #
-# version: 0.15.20230312
+# version: 0.19.20250506
 #
-# REGENDATA ("0.15.20230312",["github","cabal.project"])
+# REGENDATA ("0.19.20250506",["github","cabal.project"])
 #
 name: Haskell-CI
 on:
@@ -26,28 +26,44 @@ on:
 jobs:
   linux:
     name: Haskell-CI - Linux - ${{ matrix.compiler }}
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-24.04
     timeout-minutes:
       60
     container:
-      image: buildpack-deps:bionic
+      image: buildpack-deps:jammy
     continue-on-error: ${{ matrix.allow-failure }}
     strategy:
       matrix:
         include:
-          - compiler: ghc-9.6.1
+          - compiler: ghc-9.12.2
             compilerKind: ghc
-            compilerVersion: 9.6.1
+            compilerVersion: 9.12.2
             setup-method: ghcup
             allow-failure: false
-          - compiler: ghc-9.4.4
+          - compiler: ghc-9.10.2
             compilerKind: ghc
-            compilerVersion: 9.4.4
+            compilerVersion: 9.10.2
             setup-method: ghcup
             allow-failure: false
-          - compiler: ghc-9.2.7
+          - compiler: ghc-9.8.4
             compilerKind: ghc
-            compilerVersion: 9.2.7
+            compilerVersion: 9.8.4
+            setup-method: ghcup
+            allow-failure: false
+            upload: true
+          - compiler: ghc-9.6.7
+            compilerKind: ghc
+            compilerVersion: 9.6.7
+            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
@@ -55,7 +71,6 @@ jobs:
             compilerVersion: 9.0.2
             setup-method: ghcup
             allow-failure: false
-            upload: true
           - compiler: ghc-8.10.7
             compilerKind: ghc
             compilerVersion: 8.10.7
@@ -64,36 +79,39 @@ jobs:
           - compiler: ghc-8.8.4
             compilerKind: ghc
             compilerVersion: 8.8.4
-            setup-method: hvr-ppa
+            setup-method: ghcup
             allow-failure: false
           - compiler: ghc-8.6.5
             compilerKind: ghc
             compilerVersion: 8.6.5
-            setup-method: hvr-ppa
+            setup-method: ghcup
             allow-failure: false
       fail-fast: false
     steps:
-      - name: apt
+      - name: apt-get install
         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 "$HOME/.ghcup/bin"
-            curl -sL https://downloads.haskell.org/ghcup/0.1.18.0/x86_64-linux-ghcup-0.1.18.0 > "$HOME/.ghcup/bin/ghcup"
-            chmod a+x "$HOME/.ghcup/bin/ghcup"
-            "$HOME/.ghcup/bin/ghcup" install ghc "$HCVER" || (cat "$HOME"/.ghcup/logs/*.* && false)
-            "$HOME/.ghcup/bin/ghcup" install cabal 3.10.1.0 || (cat "$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/0.1.18.0/x86_64-linux-ghcup-0.1.18.0 > "$HOME/.ghcup/bin/ghcup"
-            chmod a+x "$HOME/.ghcup/bin/ghcup"
-            "$HOME/.ghcup/bin/ghcup" install cabal 3.10.1.0 || (cat "$HOME"/.ghcup/logs/*.* && false)
-          fi
+          apt-get install -y libx11-dev libxext-dev libxinerama-dev libxrandr-dev libxss-dev
+      - name: Install GHCup
+        run: |
+          mkdir -p "$HOME/.ghcup/bin"
+          curl -sL https://downloads.haskell.org/ghcup/0.1.50.1/x86_64-linux-ghcup-0.1.50.1 > "$HOME/.ghcup/bin/ghcup"
+          chmod a+x "$HOME/.ghcup/bin/ghcup"
+      - name: Install cabal-install
+        run: |
+          "$HOME/.ghcup/bin/ghcup" install cabal 3.14.2.0 || (cat "$HOME"/.ghcup/logs/*.* && false)
+          echo "CABAL=$HOME/.ghcup/bin/cabal-3.14.2.0 -vnormal+nowrap" >> "$GITHUB_ENV"
+      - name: Install GHC (GHCup)
+        if: matrix.setup-method == 'ghcup'
+        run: |
+          "$HOME/.ghcup/bin/ghcup" install ghc "$HCVER" || (cat "$HOME"/.ghcup/logs/*.* && false)
+          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"
         env:
           HCKIND: ${{ matrix.compilerKind }}
           HCNAME: ${{ matrix.compiler }}
@@ -104,28 +122,12 @@ jobs:
           echo "LANG=C.UTF-8" >> "$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/$HCKIND-$HCVER
-            echo "HC=$HC" >> "$GITHUB_ENV"
-            echo "HCPKG=$HOME/.ghcup/bin/$HCKIND-pkg-$HCVER" >> "$GITHUB_ENV"
-            echo "HADDOCK=$HOME/.ghcup/bin/haddock-$HCVER" >> "$GITHUB_ENV"
-            echo "CABAL=$HOME/.ghcup/bin/cabal-3.10.1.0 -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=$HOME/.ghcup/bin/cabal-3.10.1.0 -vnormal+nowrap" >> "$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 }}
@@ -168,14 +170,14 @@ jobs:
       - name: install cabal-plan
         run: |
           mkdir -p $HOME/.cabal/bin
-          curl -sL https://github.com/haskell-hvr/cabal-plan/releases/download/v0.6.2.0/cabal-plan-0.6.2.0-x86_64-linux.xz > cabal-plan.xz
-          echo 'de73600b1836d3f55e32d80385acc055fd97f60eaa0ab68a755302685f5d81bc  cabal-plan.xz' | sha256sum -c -
+          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
+        uses: actions/checkout@v4
         with:
           path: source
       - name: initial cabal.project for sdist
@@ -207,7 +209,7 @@ jobs:
           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
+          $HCPKG list --simple-output --names-only | perl -ne 'for (split /\s+/) { print "constraints: any.$_ installed\n" unless /^(xmonad)$/; }' >> cabal.project.local
           cat cabal.project
           cat cabal.project.local
       - name: dump install plan
@@ -215,7 +217,7 @@ jobs:
           $CABAL v2-build $ARG_COMPILER $ARG_TESTS $ARG_BENCH --dry-run all
           cabal-plan
       - name: restore cache
-        uses: actions/cache/restore@v3
+        uses: actions/cache/restore@v4
         with:
           key: ${{ runner.os }}-${{ matrix.compiler }}-${{ github.sha }}
           path: ~/.cabal/store
@@ -238,6 +240,10 @@ jobs:
           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
@@ -245,20 +251,25 @@ jobs:
           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()
+        uses: actions/cache/save@v4
         with:
           key: ${{ runner.os }}-${{ matrix.compiler }}-${{ github.sha }}
           path: ~/.cabal/store
-      - name: upload artifacts (sdist)
+      # must be separate artifacts because GitHub Actions are still broken:
+      # https://github.com/actions/upload-artifact/issues/441
+      # https://github.com/actions/upload-artifact/issues/457
+      - name: upload artifact (sdist)
         if: matrix.upload
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
+          name: sdist
           path: ${{ github.workspace }}/sdist/*.tar.gz
-      - name: upload artifacts (haddock)
+      - name: upload artifact (haddock)
         if: matrix.upload
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
+          name: haddock
           path: ${{ github.workspace }}/haddock/*-docs.tar.gz
       - name: hackage upload (candidate)
         if: matrix.upload && github.event_name == 'workflow_dispatch' && github.event.inputs.version != ''

.github/workflows/hlint.yaml

@@ -8,15 +8,15 @@ jobs:
   hlint:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
 
     - name: 'Set up HLint'
-      uses: haskell/actions/hlint-setup@v2
+      uses: haskell-actions/hlint-setup@v2
       with:
         version: '3.5'
 
     - name: 'Run HLint'
-      uses: haskell/actions/hlint-run@v2
+      uses: haskell-actions/hlint-run@v2
       with:
         path: '.'
         fail-on: status

.github/workflows/nix.yml

@@ -6,20 +6,16 @@ on:
 
 jobs:
   build:
-    runs-on: ubuntu-20.04  # FIXME
+    runs-on: ubuntu-latest
     name: Nix Flake - Linux
     permissions:
       contents: read
     steps:
       - name: Install Nix
-        uses: cachix/install-nix-action@v18
+        uses: cachix/install-nix-action@v31
         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 }}
+          github_access_token: ${{ secrets.GITHUB_TOKEN }}
       - name: Clone project
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
       - name: Build
         run: nix build --print-build-logs

.github/workflows/packdeps.yml

@@ -13,16 +13,15 @@ jobs:
 
     steps:
       - name: Clone project
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
       - name: Setup Haskell
-        uses: haskell/actions/setup@v2
+        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
-          echo "$HOME/.cabal/bin" >> $GITHUB_PATH
           cd  # go somewhere without a cabal.project
           cabal install packdeps
       - name: Check package bounds (all)
@@ -41,10 +40,9 @@ jobs:
             *.cabal
 
   workflow-keepalive:
+    if: github.event_name == 'schedule'
     runs-on: ubuntu-latest
+    permissions:
+      actions: write
     steps:
-      - name: Re-enable workflow
-        env:
-          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-        run: |
-          gh api -X PUT repos/${{ github.repository }}/actions/workflows/packdeps.yml/enable
+      - uses: liskin/gh-workflow-keepalive@v1

.github/workflows/stack.yml

@@ -17,10 +17,13 @@ jobs:
           - resolver: lts-18  # GHC 8.10
           - resolver: lts-19  # GHC 9.0
           - resolver: lts-20  # GHC 9.2
+          - resolver: lts-21  # GHC 9.4
+          - resolver: lts-22  # GHC 9.6
+          - resolver: lts-23  # GHC 9.8
 
     steps:
       - name: Clone project
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: Install C dependencies
         run: |
@@ -44,13 +47,13 @@ jobs:
           date +date=1-%Y-%m >> $GITHUB_OUTPUT
 
       - name: Cache Haskell package metadata
-        uses: actions/cache@v3
+        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@v3
+        uses: actions/cache@v4
         with:
           path: |
             ~/.stack/*

.gitignore

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

.mailmap

@@ -35,4 +35,5 @@ 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>
+Tony Zorman <soliditsallgood@mailbox.org> <50166980+slotThe@users.noreply.github.com>
+Tony Zorman <soliditsallgood@mailbox.org>

CHANGES.md

@@ -1,5 +1,57 @@
 # Change Log / Release Notes
 
+## _unreleased_
+
+### Breaking Changes
+
+ * Use `cabal` for `--recompile` if there is a `.cabal` file in the config
+   directory and none of `build`, `stack.yaml`, `flake.nix`, nor `default.nix`
+   exist.
+
+### Enhancements
+
+### Bug Fixes
+
+### Other
+
+PR #404 (see last change in 0.17.1) has been reverted, because the affected
+compilers are (hopefully) no longer being used.
+
+All 9.0 releases of GHC, plus 9.2.1 and 9.2.2 have the join point bug.
+Note that 9.0.x is known to also have GC issues and is officially deprecated,
+and the only 9.2 release that should be used is 9.2.8. Additionally, GHC HQ
+doesn't support releases before 9.6.6.
+
+## 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
@@ -14,6 +66,9 @@
 
   * 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
@@ -71,9 +126,6 @@
   * Added `withUnfocused` function to `XMonad.Operations`, allowing for `X`
     operations to be applied to unfocused windows.
 
-  * Added `willFloat` function to `XMonad.ManageHooks` to detect whether the
-    (about to be) managed window will be a floating window or not
-
 [these build scripts]: https://github.com/xmonad/xmonad-testing/tree/master/build-scripts
 
 ### Bug Fixes

INSTALL.md

@@ -123,7 +123,9 @@ Unless you already know which one you prefer, use Stack, which is easier.
 
 #### Install Stack
 
-The easiest way to get [stack] is probably via your system's package
+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
@@ -145,9 +147,6 @@ stack via its [documentation][stack]):
 $ curl -sSL https://get.haskellstack.org/ | sh
 ```
 
-Yet another way would be via [ghcup]; this is similar to installers like
-`rustup`, in case you prefer that.
-
 #### Create a New Project
 
 Let's create a stack project.  Since we're already in the correct
@@ -222,7 +221,9 @@ be that you don't have the required C libraries installed.  See
 
 #### Install cabal-install
 
-The easiest way to get [cabal-install] is probably via your system's package
+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
@@ -231,22 +232,22 @@ $ sudo dnf install cabal-install    # Fedora
 $ sudo pacman -S cabal-install      # Arch
 ```
 
-If your distribution does not package cabal-install, [ghcup][] is another
-option.  See also <https://www.haskell.org/cabal/#install-upgrade>.
+See also <https://www.haskell.org/cabal/#install-upgrade>.
 
 #### Create a New Project
 
-Let's create a cabal project.  Since we're already in the correct
-directory (`~/.config/xmonad`) with `xmonad` and `xmonad-contrib`
-subdirectories, we'll instruct cabal to use them.  Create a file named
-`cabal.project` containing:
+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 skip this step, cabal will use the latest releases from [Hackage][]
-instead.)
+(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
 
@@ -255,7 +256,7 @@ libraries and then build the xmonad binary:
 
 ``` console
 $ cabal update
-$ cabal install --package-env=$HOME/.config/xmonad --lib xmonad xmonad-contrib
+$ cabal install --package-env=$HOME/.config/xmonad --lib base xmonad xmonad-contrib
 $ cabal install --package-env=$HOME/.config/xmonad xmonad
 ```
 
@@ -393,7 +394,9 @@ executable will also be within that directory and not in
 [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/
+[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

MAINTAINERS.md

@@ -117,7 +117,12 @@ When the time comes to release another version of xmonad and xmonad-contrib:
 
      See [old announcements][old-announce] ([even older][older-announce]) for inspiration.
 
-  7. Bump version for development (add `.9`) and prepare fresh sections in
+  7. Trigger xmonad-docs build to generate and persist docs for the just
+     released version:
+
+     - https://github.com/xmonad/xmonad-docs/actions/workflows/stack.yml
+
+  8. Bump version for development (add `.9`) and prepare fresh sections in
      [`CHANGES.md`](CHANGES.md).
 
 [packdeps]: https://hackage.haskell.org/package/packdeps

README.md

@@ -6,9 +6,9 @@
   <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/workflow/status/xmonad/xmonad/Stack?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/workflow/status/xmonad/xmonad/Haskell-CI?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/workflow/status/xmonad/xmonad/Nix?label=Nix&logo=githubactions&logoColor=white"></a>
+  <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>

TUTORIAL.md

@@ -38,13 +38,13 @@ package manager, you will need to `xmonad --recompile` _every time_ a
 Haskell dependency is updated—else xmonad may fail to start when you
 want to log in!
 
-We're going to assume xmonad version `0.17.0` and xmonad-contrib version
-`0.17.0` here, though most of these steps should work with older
-versions as well.  When we get to the relevant parts, will point you to
-alternatives that work with at least xmonad version `0.15` and
-xmonad-contrib version `0.16`.  This will usually be accompanied by a
-big "_IF YOU ARE ON A VERSION `< 0.17.0`_", so don't worry about missing
-it!
+We're going to assume xmonad version `>= 0.17.0` and xmonad-contrib
+version `>= 0.17.0` here, though most of these steps should work with
+older versions as well. When we get to the relevant parts, will point
+you to alternatives that work with at least xmonad version `0.15` and
+xmonad-contrib version `0.16`. This will usually be accompanied by big
+warning labels for the respective version bounds, so don't worry about
+missing it!
 
 Throughout the tutorial we will use, for keybindings, a syntax very akin
 to the [GNU Emacs conventions] for the same thing—so `C-x` means "hold
@@ -77,6 +77,11 @@ a live xmonad session in some capacity.  If you have set up your
 `~/.xinitrc` as directed in the xmonad guided tour, you should be good
 to go!  If not, just smack an `exec xmonad` at the bottom of that file.
 
+In particular, it might be a good idea to set a wallpaper beforehand.
+Otherwise, when switching workspaces or closing windows, you might start
+seeing "shadows" of windows that were there before, unable to interact
+with them.
+
 ## Installing Xmobar
 
 What we need to do now—provided we want to use a bar at all—is to
@@ -108,6 +113,8 @@ utility modules we will use.  At the very top of the file, write
 import XMonad
 
 import XMonad.Util.EZConfig
+-- NOTE: Only needed for versions < 0.18.0! For 0.18.0 and up, this is
+-- already included in the XMonad import and will give you a warning!
 import XMonad.Util.Ungrab
 ```
 
@@ -263,7 +270,7 @@ myLayout = tiled ||| Mirror tiled ||| Full
 ```
 
 The so-called `where`-clause above simply consists of local declarations
-that might clutter things up where they all declared at the top-level
+that might clutter things up were they all declared at the top-level
 like this
 
 ``` haskell
@@ -379,12 +386,16 @@ effect (and some applications, like chromium, will misbehave and need
 some [Hacks] to make this work), we will also add the relevant function
 to get "proper" fullscreen behaviour here.
 
+---
+
 _IF YOU ARE ON A VERSION `< 0.17.0`_: The `ewmhFullscreen` function does
   not exist in these versions.  Instead of it, you can try to add
   `fullscreenEventHook` to your `handleEventHook` to achieve similar
   functionality (how to do this is explained in the documentation of
   [XMonad.Hooks.EwmhDesktops]).
 
+---
+
 To use the two combinators, we compose them with the `xmonad` function
 in the following way:
 
@@ -430,7 +441,7 @@ Much better!
 ## Make XMonad and Xmobar Talk to Each Other
 
 Onto the main dish.  First, we have to import the necessary modules.
-Add the following to your list of imports:
+Add the following to your list of imports
 
 ``` haskell
 import XMonad.Hooks.DynamicLog
@@ -438,23 +449,27 @@ import XMonad.Hooks.StatusBar
 import XMonad.Hooks.StatusBar.PP
 ```
 
-_IF YOU ARE ON A VERSION `< 0.17.0`_: The `XMonad.Hooks.StatusBar` and
-  `XMonad.Hooks.StatusBar.PP` modules don't exist yet.  You can find
-  everything you need in the `XMonad.Hooks.DynamicLog` module, so remove
-  these two imports.
-
-Replace your `main` function above with:
+and replace your `main` function above with:
 
 ``` haskell
 main :: IO ()
 main = xmonad $ ewmhFullscreen $ ewmh $ xmobarProp $ myConfig
 ```
 
-_IF YOU ARE ON A VERSION `< 0.17.0`_: The `xmobarProp` function does not
-  exist in these versions.  Instead of it, use `xmobar` via
-  `main = xmonad . ewmh =<< xmobar myConfig` and carefully read the part
-  about pipes later on (`xmobar` uses pipes to make xmobar talk to
-  xmonad).
+---
+
+_IF YOU ARE ON A VERSION `< 0.17.0`_: The `XMonad.Hooks.StatusBar` and
+  `XMonad.Hooks.StatusBar.PP` modules don't exist yet.  You can find
+  everything you need in the `XMonad.Hooks.DynamicLog` module, so remove
+  these two imports.
+
+  Further, the `xmobarProp` function does not exist in older versions.
+  Instead of it, use `xmobar` via `main = xmonad . ewmh =<< xmobar
+  myConfig` and carefully read the part about pipes later on (`xmobar`
+  uses pipes to make xmobar talk to xmonad).  Do note the lack of
+  `ewmhFullscreen`, as explained above!
+
+---
 
 As a quick side-note, we could have also written
 
@@ -540,11 +555,15 @@ when things are not being read!  For this reason we have to use
 (this is useful, for example, for [XMonad.Util.ClickableWorkspaces],
 which is a new feature in `0.17.0`).
 
+---
+
 _IF YOU ARE ON A VERSION `< 0.17.0`_: As discussed above, the `xmobar`
   function uses pipes, so you actually do want to use the `StdinReader`.
   Simply replace _all_ occurences of `XMonadLog` with `StdinReader`
   below (don't forget the template!)
 
+---
+
 ## Configuring Xmobar
 
 Now, before this will work, we have to configure xmobar.  Here's a nice
@@ -660,6 +679,8 @@ main = xmonad
      $ myConfig
 ```
 
+---
+
 _IF YOU ARE ON A VERSION `< 0.17.0`_: `xmobar` has a similar definition,
   relying on `statusBar` alone: `xmobar = statusBar "xmobar" xmobarPP
     toggleStrutsKey`.  Sadly, the `defToggleStrutsKey` function is not yet
@@ -668,7 +689,6 @@ _IF YOU ARE ON A VERSION `< 0.17.0`_: `xmobar` has a similar definition,
 ``` haskell
 main :: IO ()
 main = xmonad
-     . ewmhFullscreen
      . ewmh
    =<< statusBar "xmobar" def toggleStrutsKey myConfig
   where
@@ -676,6 +696,8 @@ main = xmonad
     toggleStrutsKey XConfig{ modMask = m } = (m, xK_b)
 ```
 
+---
+
 The `defToggleStrutsKey` here is just the key with which you can toggle
 the bar; it is bound to `M-b`.  If you want to change this, you can also
 define your own:
@@ -772,6 +794,8 @@ myXmobarPP = def
     lowWhite = xmobarColor "#bbbbbb" ""
 ```
 
+---
+
 _IF YOU ARE ON A VERSION `< 0.17`_: Both `logTitles` and `xmobarBorder`
   are not available yet, so you will have to remove them.  As an
   alternative to `xmobarBorder`, a common way to "mark" the currently
@@ -779,6 +803,8 @@ _IF YOU ARE ON A VERSION `< 0.17`_: Both `logTitles` and `xmobarBorder`
   `ppCurrent = wrap (blue "[") (blue "]")` and see if you like it.  Also
   read the bit about `ppOrder` further down!
 
+---
+
 That's a lot!  But don't worry, take a deep breath and remind yourself
 of what you read above in the documentation of the [PP record].  Even if
 you haven't read the documentation yet, most of the fields should be
@@ -882,10 +908,10 @@ apt-get install nm-applet feh xfce4-power-manager
 
 First, configure xscreensaver how you like it with the
 `xscreensaver-demo` command.  Now, we will set these things up in
-`~/.xinitrc` (we could also do most of this in xmonad's `startupHook`,
-but `~/.xinitrc` is perhaps more standard).  If you want to use xmonad
-with a desktop environment, see [Basic Desktop Environment Integration]
-for how to do this.
+`~/.xinitrc`.  If you want to use XMonad with a desktop environment, see
+[Basic Desktop Environment Integration] for how to do this.  For a
+version using XMonad's built in functionality instead, see the [next
+section][using-the-startupHook].
 
 Your `~/.xinitrc` may wind up looking like this:
 
@@ -933,6 +959,38 @@ Mission accomplished!
 Of course substitute the wallpaper for one of your own.  If you like the
 one used above, you can find it [here](https://i.imgur.com/9MQHuZx.png).
 
+### Using the `startupHook`
+
+Instead of the `.xinitrc` file, one can also use XMonad's built in
+`startupHook` in order to auto start programs.  The
+[XMonad.Util.SpawnOnce] library is perfect for this use case, allowing
+programs to start only once, and not with every invocation of `M-q`!
+
+This requires but a small change in `myConfig`:
+
+``` haskell
+-- import XMonad.Util.SpawnOnce (spawnOnce)
+
+myConfig = def
+    { modMask     = mod4Mask       -- Rebind Mod to the Super key
+    , layoutHook  = myLayout       -- Use custom layouts
+    , startupHook = myStartupHook
+    }
+  `additionalKeysP`
+    [ ("M-S-z", spawn "xscreensaver-command -lock")
+    , ("M-C-s", unGrab *> spawn "scrot -s"        )
+    , ("M-f"  , spawn "firefox"                   )
+    ]
+
+myStartupHook :: X ()
+myStartupHook = do
+  spawnOnce "trayer --edge top --align right --SetDockType true \
+            \--SetPartialStrut true --expand true --width 10 \
+            \--transparent true --tint 0x5f5f5f --height 18"
+  spawnOnce "feh --bg-fill --no-fehbg ~/.wallpapers/haskell-red-noise.png"
+  -- … and so on …
+```
+
 ## Final Touches
 
 There may be some programs that you don't want xmonad to tile.  The
@@ -1010,6 +1068,9 @@ import XMonad.Hooks.StatusBar.PP
 
 import XMonad.Util.EZConfig
 import XMonad.Util.Loggers
+-- NOTE: Importing XMonad.Util.Ungrab is only necessary for versions
+-- < 0.18.0! For 0.18.0 and up, this is already included in the
+-- XMonad import and will generate a warning instead!
 import XMonad.Util.Ungrab
 
 import XMonad.Layout.Magnifier
@@ -1238,21 +1299,22 @@ either :)
 [Basic Desktop Environment Integration]: https://wiki.haskell.org/Xmonad/Basic_Desktop_Environment_Integration
 
 [Hacks]: https://xmonad.github.io/xmonad-docs/xmonad-contrib/XMonad-Util-Hacks.html
-[PP record]: https://xmonad.github.io/xmonad-docs/xmonad-contrib/XMonad-Hooks-DynamicLog.html#t:PP
 [INSTALL.md]: INSTALL.md
+[PP record]: https://xmonad.github.io/xmonad-docs/xmonad-contrib/XMonad-Hooks-DynamicLog.html#t:PP
 [XMonad.Config]: https://github.com/xmonad/xmonad/blob/master/src/XMonad/Config.hs
-[XMonad.ManageHook]: https://xmonad.github.io/xmonad-docs/xmonad/XMonad-ManageHook.html
-[XMonad.Util.Loggers]: https://xmonad.github.io/xmonad-docs/xmonad-contrib/XMonad-Util-Loggers.html
-[XMonad.Util.EZConfig]: https://xmonad.github.io/xmonad-docs/xmonad-contrib/XMonad-Util-EZConfig.html
-[XMonad.Layout.Renamed]: https://xmonad.github.io/xmonad-docs/xmonad-contrib/XMonad-Layout-Renamed.html
-[XMonad.Layout.Magnifier]: https://xmonad.github.io/xmonad-docs/xmonad-contrib/XMonad-Layout-Magnifier.html
 [XMonad.Doc.Contributing]: https://xmonad.github.io/xmonad-docs/xmonad-contrib/XMonad-Doc-Configuring.html
 [XMonad.Hooks.EwmhDesktops]: https://xmonad.github.io/xmonad-docs/xmonad-contrib/XMonad-Hooks-EwmhDesktops.html
-[XMonad.Layout.ThreeColumns]: https://xmonad.github.io/xmonad-docs/xmonad-contrib/XMonad-Layout-ThreeColumns.html
 [XMonad.Hooks.ManageHelpers]: https://xmonad.github.io/xmonad-docs/xmonad-contrib/XMonad-Hooks-ManageHelpers.html
+[XMonad.Layout.Magnifier]: https://xmonad.github.io/xmonad-docs/xmonad-contrib/XMonad-Layout-Magnifier.html
+[XMonad.Layout.Renamed]: https://xmonad.github.io/xmonad-docs/xmonad-contrib/XMonad-Layout-Renamed.html
+[XMonad.Layout.ThreeColumns]: https://xmonad.github.io/xmonad-docs/xmonad-contrib/XMonad-Layout-ThreeColumns.html
+[XMonad.ManageHook]: https://xmonad.github.io/xmonad-docs/xmonad/XMonad-ManageHook.html
 [XMonad.Util.ClickableWorkspaces]: https://xmonad.github.io/xmonad-docs/xmonad-contrib/XMonad-Util-ClickableWorkspaces.html
+[XMonad.Util.EZConfig]: https://xmonad.github.io/xmonad-docs/xmonad-contrib/XMonad-Util-EZConfig.html
+[XMonad.Util.Loggers]: https://xmonad.github.io/xmonad-docs/xmonad-contrib/XMonad-Util-Loggers.html
+[XMonad.Util.SpawnOnce]: https://hackage.haskell.org/package/xmonad-contrib/docs/XMonad-Util-SpawnOnce.html
 
-[xmobar]: https://xmobar.org/
+[xmobar]: https://codeberg.org/xmobar/xmobar
 [battery]: https://codeberg.org/xmobar/xmobar/src/branch/master/doc/plugins.org#batteryp-dirs-args-refreshrate
 [xmobar.hs]: https://codeberg.org/xmobar/xmobar/src/branch/master/etc/xmobar.hs
 [Wikipedia page]: https://en.wikipedia.org/wiki/ICAO_airport_code#Prefixes

flake.nix

@@ -2,9 +2,9 @@
 # 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;
+    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
@@ -15,17 +15,26 @@
        else [ "haskell" "packages" compiler ]
       );
     fromHOL = hol: comp: final: prev: with prev.lib; with attrsets;
-      setAttrByPath (hpath comp)
-        ((getAttrFromPath (hpath comp) prev).override (old: {
+      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 ./.) { };
       };
-    overlay = fromHOL hoverlay { };
+    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
@@ -37,7 +46,7 @@
             enable = mkEnableOption "flake";
             prefix = mkOption {
               default = null;
-              type = nullOr string;
+              type = nullOr str;
               example = literalExpression "\"unstable\"";
               description = ''
                 Specify a nested alternative <literal>pkgs</literal> by attrName.
@@ -45,7 +54,7 @@
             };
             compiler = mkOption {
               default = null;
-              type = nullOr string;
+              type = nullOr str;
               example = literalExpression "\"ghc922\"";
               description = ''
                 Which compiler to build xmonad with.
@@ -64,12 +73,32 @@
     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 = pkgs.haskellPackages.shellFor {
+    devShell = hpkg.shellFor (modifyDevShell pkgs {
       packages = p: [ p.xmonad ];
-    };
-    defaultPackage = pkgs.haskellPackages.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/xmonad.1

@@ -1,5 +1,19 @@
-.\" Automatically generated by Pandoc 2.9.2.1
+.\" Automatically generated by Pandoc 3.1.3
 .\"
+.\" Define V font for inline verbatim, using C font in formats
+.\" that render this, and otherwise B font.
+.ie "\f[CB]x\f[]"x" \{\
+. ftr V B
+. ftr VI BI
+. ftr VB B
+. ftr VBI BI
+.\}
+.el \{\
+. ftr V CR
+. ftr VI CI
+. ftr VB CB
+. ftr VBI CBI
+.\}
 .TH "XMONAD" "1" "27 October 2021" "Tiling Window Manager" ""
 .hy
 .SH Name
@@ -191,15 +205,15 @@ 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].
+Setting \f[V]XMONAD_DATA_DIR,\f[R] \f[V]XMONAD_CONFIG_DIR\f[R], and
+\f[V]XMONAD_CACHE_DIR\f[R]; \f[I]xmonad.hs\f[R] is then expected to be
+in \f[V]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.
+Creating \f[I]xmonad.hs\f[R] in \f[V]XDG_CONFIG_HOME\f[R].
+Note that, in this case, xmonad will use \f[V]XDG_DATA_HOME\f[R] and
+\f[V]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-
 contrib package, available through your package manager or from

man/xmonad.1.html

@@ -8,15 +8,167 @@
   <meta name="dcterms.date" content="2021-10-27" />
   <title>XMONAD(1) Tiling Window Manager</title>
   <style>
+    html {
+      color: #1a1a1a;
+      background-color: #fdfdfd;
+    }
+    body {
+      margin: 0 auto;
+      max-width: 36em;
+      padding-left: 50px;
+      padding-right: 50px;
+      padding-top: 50px;
+      padding-bottom: 50px;
+      hyphens: auto;
+      overflow-wrap: break-word;
+      text-rendering: optimizeLegibility;
+      font-kerning: normal;
+    }
+    @media (max-width: 600px) {
+      body {
+        font-size: 0.9em;
+        padding: 12px;
+      }
+      h1 {
+        font-size: 1.8em;
+      }
+    }
+    @media print {
+      html {
+        background-color: white;
+      }
+      body {
+        background-color: transparent;
+        color: black;
+        font-size: 12pt;
+      }
+      p, h2, h3 {
+        orphans: 3;
+        widows: 3;
+      }
+      h2, h3, h4 {
+        page-break-after: avoid;
+      }
+    }
+    p {
+      margin: 1em 0;
+    }
+    a {
+      color: #1a1a1a;
+    }
+    a:visited {
+      color: #1a1a1a;
+    }
+    img {
+      max-width: 100%;
+    }
+    h1, h2, h3, h4, h5, h6 {
+      margin-top: 1.4em;
+    }
+    h5, h6 {
+      font-size: 1em;
+      font-style: italic;
+    }
+    h6 {
+      font-weight: normal;
+    }
+    ol, ul {
+      padding-left: 1.7em;
+      margin-top: 1em;
+    }
+    li > ol, li > ul {
+      margin-top: 0;
+    }
+    blockquote {
+      margin: 1em 0 1em 1.7em;
+      padding-left: 1em;
+      border-left: 2px solid #e6e6e6;
+      color: #606060;
+    }
+    code {
+      font-family: Menlo, Monaco, Consolas, 'Lucida Console', monospace;
+      font-size: 85%;
+      margin: 0;
+      hyphens: manual;
+    }
+    pre {
+      margin: 1em 0;
+      overflow: auto;
+    }
+    pre code {
+      padding: 0;
+      overflow: visible;
+      overflow-wrap: normal;
+    }
+    .sourceCode {
+     background-color: transparent;
+     overflow: visible;
+    }
+    hr {
+      background-color: #1a1a1a;
+      border: none;
+      height: 1px;
+      margin: 1em 0;
+    }
+    table {
+      margin: 1em 0;
+      border-collapse: collapse;
+      width: 100%;
+      overflow-x: auto;
+      display: block;
+      font-variant-numeric: lining-nums tabular-nums;
+    }
+    table caption {
+      margin-bottom: 0.75em;
+    }
+    tbody {
+      margin-top: 0.5em;
+      border-top: 1px solid #1a1a1a;
+      border-bottom: 1px solid #1a1a1a;
+    }
+    th {
+      border-top: 1px solid #1a1a1a;
+      padding: 0.25em 0.5em 0.25em 0.5em;
+    }
+    td {
+      padding: 0.125em 0.5em 0.25em 0.5em;
+    }
+    header {
+      margin-bottom: 4em;
+      text-align: center;
+    }
+    #TOC li {
+      list-style: none;
+    }
+    #TOC ul {
+      padding-left: 1.3em;
+    }
+    #TOC > ul {
+      padding-left: 0;
+    }
+    #TOC a:not(:hover) {
+      text-decoration: none;
+    }
     code{white-space: pre-wrap;}
     span.smallcaps{font-variant: small-caps;}
-    span.underline{text-decoration: underline;}
-    div.column{display: inline-block; vertical-align: top; width: 50%;}
+    div.columns{display: flex; gap: min(4vw, 1.5em);}
+    div.column{flex: auto; overflow-x: auto;}
     div.hanging-indent{margin-left: 1.5em; text-indent: -1.5em;}
-    ul.task-list{list-style: none;}
+    /* The extra [class] is a hack that increases specificity enough to
+       override a similar rule in reveal.js */
+    ul.task-list[class]{list-style: none;}
+    ul.task-list li input[type="checkbox"] {
+      font-size: inherit;
+      width: 0.8em;
+      margin: 0 0.8em 0.2em -1.6em;
+      vertical-align: middle;
+    }
+    .display.math{display: block; text-align: center; margin: 0.5rem auto;}
+    /* CSS for syntax highlighting */
     pre > code.sourceCode { white-space: pre; position: relative; }
-    pre > code.sourceCode > span { display: inline-block; line-height: 1.25; }
+    pre > code.sourceCode > span { line-height: 1.25; }
     pre > code.sourceCode > span:empty { height: 1.2em; }
+    .sourceCode { overflow: visible; }
     code.sourceCode > span { color: inherit; text-decoration: inherit; }
     div.sourceCode { margin: 1em 0; }
     pre.sourceCode { margin: 0; }
@@ -51,7 +203,7 @@
     code span.an { color: #60a0b0; font-weight: bold; font-style: italic; } /* Annotation */
     code span.at { color: #7d9029; } /* Attribute */
     code span.bn { color: #40a070; } /* BaseN */
-    code span.bu { } /* BuiltIn */
+    code span.bu { color: #008000; } /* BuiltIn */
     code span.cf { color: #007020; font-weight: bold; } /* ControlFlow */
     code span.ch { color: #4070a0; } /* Char */
     code span.cn { color: #880000; } /* Constant */
@@ -64,7 +216,7 @@
     code span.ex { } /* Extension */
     code span.fl { color: #40a070; } /* Float */
     code span.fu { color: #06287e; } /* Function */
-    code span.im { } /* Import */
+    code span.im { color: #008000; font-weight: bold; } /* Import */
     code span.in { color: #60a0b0; font-weight: bold; font-style: italic; } /* Information */
     code span.kw { color: #007020; font-weight: bold; } /* Keyword */
     code span.op { color: #666666; } /* Operator */
@@ -86,165 +238,253 @@
 </header>
 <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>
+<li><a href="#name" id="toc-name">Name</a></li>
+<li><a href="#description" id="toc-description">Description</a></li>
+<li><a href="#usage" id="toc-usage">Usage</a>
 <ul>
-<li><a href="#flags">Flags</a></li>
-<li><a href="#default-keyboard-bindings">Default keyboard bindings</a></li>
+<li><a href="#flags" id="toc-flags">Flags</a></li>
+<li><a href="#default-keyboard-bindings"
+id="toc-default-keyboard-bindings">Default keyboard bindings</a></li>
 </ul></li>
-<li><a href="#examples">Examples</a></li>
-<li><a href="#customization">Customization</a>
+<li><a href="#examples" id="toc-examples">Examples</a></li>
+<li><a href="#customization" id="toc-customization">Customization</a>
 <ul>
-<li><a href="#modular-configuration">Modular Configuration</a></li>
+<li><a href="#modular-configuration"
+id="toc-modular-configuration">Modular Configuration</a></li>
 </ul></li>
-<li><a href="#bugs">Bugs</a></li>
+<li><a href="#bugs" id="toc-bugs">Bugs</a></li>
 </ul>
 </nav>
 <h1 id="name">Name</h1>
 <p>xmonad - Tiling Window Manager</p>
 <h1 id="description">Description</h1>
-<p><em>xmonad</em> 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. <em>xmonad</em> is configured in Haskell, and custom layout algorithms may be implemented by the user in config files. A principle of <em>xmonad</em> is predictability: the user should know in advance precisely the window arrangement that will result from any action.</p>
-<p>By default, <em>xmonad</em> 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.</p>
-<p>By utilizing the expressivity of a modern functional language with a rich static type system, <em>xmonad</em> 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.</p>
+<p><em>xmonad</em> 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. <em>xmonad</em> is configured in Haskell, and custom layout
+algorithms may be implemented by the user in config files. A principle
+of <em>xmonad</em> is predictability: the user should know in advance
+precisely the window arrangement that will result from any action.</p>
+<p>By default, <em>xmonad</em> 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.</p>
+<p>By utilizing the expressivity of a modern functional language with a
+rich static type system, <em>xmonad</em> 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.</p>
 <h1 id="usage">Usage</h1>
-<p><em>xmonad</em> 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.</p>
-<p>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.</p>
-<p>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 <em>xmonad</em> 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.</p>
+<p><em>xmonad</em> 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.</p>
+<p>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.</p>
+<p>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 <em>xmonad</em> 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.</p>
 <h2 id="flags">Flags</h2>
-<p>xmonad has several flags which you may pass to the executable. These flags are:</p>
+<p>xmonad has several flags which you may pass to the executable. These
+flags are:</p>
 <dl>
 <dt>–recompile</dt>
-<dd>Recompiles your <em>xmonad.hs</em> configuration
+<dd>
+Recompiles your <em>xmonad.hs</em> configuration
 </dd>
 <dt>–restart</dt>
-<dd>Causes the currently running <em>xmonad</em> process to restart
+<dd>
+Causes the currently running <em>xmonad</em> process to restart
 </dd>
 <dt>–replace</dt>
-<dd>Replace the current window manager with xmonad
+<dd>
+Replace the current window manager with xmonad
 </dd>
 <dt>–version</dt>
-<dd>Display version of <em>xmonad</em>
+<dd>
+Display version of <em>xmonad</em>
 </dd>
 <dt>–verbose-version</dt>
-<dd>Display detailed version of <em>xmonad</em>
+<dd>
+Display detailed version of <em>xmonad</em>
 </dd>
 </dl>
 <h2 id="default-keyboard-bindings">Default keyboard bindings</h2>
 <dl>
 <dt>mod-shift-return</dt>
-<dd>Launch terminal
+<dd>
+Launch terminal
 </dd>
 <dt>mod-p</dt>
-<dd>Launch dmenu
+<dd>
+Launch dmenu
 </dd>
 <dt>mod-shift-p</dt>
-<dd>Launch gmrun
+<dd>
+Launch gmrun
 </dd>
 <dt>mod-shift-c</dt>
-<dd>Close the focused window
+<dd>
+Close the focused window
 </dd>
 <dt>mod-space</dt>
-<dd>Rotate through the available layout algorithms
+<dd>
+Rotate through the available layout algorithms
 </dd>
 <dt>mod-shift-space</dt>
-<dd>Reset the layouts on the current workspace to default
+<dd>
+Reset the layouts on the current workspace to default
 </dd>
 <dt>mod-n</dt>
-<dd>Resize viewed windows to the correct size
+<dd>
+Resize viewed windows to the correct size
 </dd>
 <dt>mod-tab</dt>
-<dd>Move focus to the next window
+<dd>
+Move focus to the next window
 </dd>
 <dt>mod-shift-tab</dt>
-<dd>Move focus to the previous window
+<dd>
+Move focus to the previous window
 </dd>
 <dt>mod-j</dt>
-<dd>Move focus to the next window
+<dd>
+Move focus to the next window
 </dd>
 <dt>mod-k</dt>
-<dd>Move focus to the previous window
+<dd>
+Move focus to the previous window
 </dd>
 <dt>mod-m</dt>
-<dd>Move focus to the master window
+<dd>
+Move focus to the master window
 </dd>
 <dt>mod-return</dt>
-<dd>Swap the focused window and the master window
+<dd>
+Swap the focused window and the master window
 </dd>
 <dt>mod-shift-j</dt>
-<dd>Swap the focused window with the next window
+<dd>
+Swap the focused window with the next window
 </dd>
 <dt>mod-shift-k</dt>
-<dd>Swap the focused window with the previous window
+<dd>
+Swap the focused window with the previous window
 </dd>
 <dt>mod-h</dt>
-<dd>Shrink the master area
+<dd>
+Shrink the master area
 </dd>
 <dt>mod-l</dt>
-<dd>Expand the master area
+<dd>
+Expand the master area
 </dd>
 <dt>mod-t</dt>
-<dd>Push window back into tiling
+<dd>
+Push window back into tiling
 </dd>
 <dt>mod-comma</dt>
-<dd>Increment the number of windows in the master area
+<dd>
+Increment the number of windows in the master area
 </dd>
 <dt>mod-period</dt>
-<dd>Deincrement the number of windows in the master area
+<dd>
+Deincrement the number of windows in the master area
 </dd>
 <dt>mod-shift-q</dt>
-<dd>Quit xmonad
+<dd>
+Quit xmonad
 </dd>
 <dt>mod-q</dt>
-<dd>Restart xmonad
+<dd>
+Restart xmonad
 </dd>
 <dt>mod-shift-slash</dt>
-<dd>Run xmessage with a summary of the default keybindings (useful for beginners)
+<dd>
+Run xmessage with a summary of the default keybindings (useful for
+beginners)
 </dd>
 <dt>mod-question</dt>
-<dd>Run xmessage with a summary of the default keybindings (useful for beginners)
+<dd>
+Run xmessage with a summary of the default keybindings (useful for
+beginners)
 </dd>
 <dt>mod-[1..9]</dt>
-<dd>Switch to workspace N
+<dd>
+Switch to workspace N
 </dd>
 <dt>mod-shift-[1..9]</dt>
-<dd>Move client to workspace N
+<dd>
+Move client to workspace N
 </dd>
 <dt>mod-{w,e,r}</dt>
-<dd>Switch to physical/Xinerama screens 1, 2, or 3
+<dd>
+Switch to physical/Xinerama screens 1, 2, or 3
 </dd>
 <dt>mod-shift-{w,e,r}</dt>
-<dd>Move client to screen 1, 2, or 3
+<dd>
+Move client to screen 1, 2, or 3
 </dd>
 <dt>mod-button1</dt>
-<dd>Set the window to floating mode and move by dragging
+<dd>
+Set the window to floating mode and move by dragging
 </dd>
 <dt>mod-button2</dt>
-<dd>Raise the window to the top of the stack
+<dd>
+Raise the window to the top of the stack
 </dd>
 <dt>mod-button3</dt>
-<dd>Set the window to floating mode and resize by dragging
+<dd>
+Set the window to floating mode and resize by dragging
 </dd>
 </dl>
 <h1 id="examples">Examples</h1>
-<p>To use xmonad as your window manager add to your <em>~/.xinitrc</em> file:</p>
+<p>To use xmonad as your window manager add to your <em>~/.xinitrc</em>
+file:</p>
 <blockquote>
 <p>exec xmonad</p>
 </blockquote>
 <h1 id="customization">Customization</h1>
-<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>
+<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>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>
+<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>
+<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"><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>
+<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"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></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" tabindex="-1"></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>
+<p>Probably. If you find any, please report them to the <a
+href="https://github.com/xmonad/xmonad/issues">bugtracker</a></p>
 </body>
 </html>

src/XMonad/Core.hs

@@ -7,6 +7,8 @@
 {-# LANGUAGE MultiParamTypeClasses #-}
 {-# LANGUAGE NamedFieldPuns #-}
 {-# LANGUAGE ScopedTypeVariables #-}
+{-# LANGUAGE DerivingVia #-}
+{-# LANGUAGE ViewPatterns #-}
 
 -----------------------------------------------------------------------------
 -- |
@@ -32,7 +34,7 @@ module XMonad.Core (
     StateExtension(..), ExtensionClass(..), ConfExtension(..),
     runX, catchX, userCode, userCodeDef, io, catchIO, installSignalHandlers, uninstallSignalHandlers,
     withDisplay, withWindowSet, isRoot, runOnWorkspaces,
-    getAtom, spawn, spawnPID, xfork, xmessage, recompile, trace, whenJust, whenX,
+    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, Directories'(..), Directories, getDirectories,
@@ -48,12 +50,14 @@ import Control.Monad.Fail
 import Control.Monad.Fix (fix)
 import Control.Monad.State
 import Control.Monad.Reader
-import Control.Monad (filterM, guard, liftM2, void, when)
+import Control.Monad (filterM, guard, void, when)
+import Data.Char (isSpace)
 import Data.Semigroup
 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
@@ -68,8 +72,8 @@ import System.Exit
 import Graphics.X11.Xlib
 import Graphics.X11.Xlib.Extras (getWindowAttributes, WindowAttributes, Event)
 import Data.Typeable
-import Data.List (isInfixOf, (\\))
 import Data.Maybe (isJust,fromMaybe)
+import Data.Monoid (Ap(..))
 
 import qualified Data.Map as M
 import qualified Data.Set as S
@@ -165,12 +169,7 @@ newtype ScreenDetail = SD { screenRect :: Rectangle }
 --
 newtype X a = X (ReaderT XConf (StateT XState IO) a)
     deriving (Functor, Applicative, Monad, MonadFail, MonadIO, MonadState XState, MonadReader XConf)
-
-instance Semigroup a => Semigroup (X a) where
-    (<>) = liftM2 (<>)
-
-instance (Monoid a) => Monoid (X a) where
-    mempty = pure mempty
+    deriving (Semigroup, Monoid) via Ap X a
 
 instance Default a => Default (X a) where
     def = return def
@@ -178,16 +177,11 @@ 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) = runReaderT m
 
-instance Semigroup a => Semigroup (Query a) where
-    (<>) = liftM2 (<>)
-
-instance Monoid a => Monoid (Query a) where
-    mempty = pure mempty
-
 instance Default a => Default (Query a) where
     def = return def
 
@@ -423,9 +417,13 @@ data StateExtension =
 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
 
@@ -584,21 +582,32 @@ srcFileName, libFileName :: Directories -> FilePath
 srcFileName Directories{ cfgDir } = cfgDir </> "xmonad.hs"
 libFileName Directories{ cfgDir } = cfgDir </> "lib"
 
-buildScriptFileName, stackYamlFileName :: Directories -> FilePath
+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 | CompileScript FilePath
+data Compile
+  = CompileGhc
+  | CompileCabal
+  | 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 <|> useGhc
+detectCompile dirs =
+  tryScript <|> tryStack <|> tryNixFlake <|> tryNixDefault <|> tryCabal <|> useGhc
   where
     buildScript = buildScriptFileName dirs
     stackYaml = stackYamlFileName dirs
+    flakeNix = nixFlakeFileName dirs
+    defaultNix = nixDefaultFileName dirs
 
     tryScript = do
         guard =<< doesFileExist buildScript
@@ -612,18 +621,58 @@ detectCompile dirs = tryScript <|> tryStack <|> useGhc
             trace $ "Suggested resolution to use it: chmod u+x " <> show buildScript
             empty
 
+    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
 
+    tryCabal = let cwd = cfgDir dirs in listCabalFiles cwd >>= \ case
+        [] -> do
+            empty
+        [name] -> do
+            trace $ "XMonad will use " <> show name <> " to recompile."
+            pure CompileCabal
+        _ : _ : _ -> do
+            trace $ "XMonad will not use cabal, because there are multiple cabal files in " <> show cwd <> "."
+            empty
+
     useGhc = do
-        trace $ "XMonad will use ghc to recompile, because neither "
-                <> show buildScript <> " nor " <> show stackYaml <> " exists."
+        trace $ "XMonad will use ghc to recompile, because none of "
+                <> intercalate ", "
+                     [ show buildScript
+                     , show stackYaml
+                     , show flakeNix
+                     , show defaultNix
+                     ] <> " nor a suitable .cabal file exist."
         pure CompileGhc
 
-    isExecutable f = E.catch (executable <$> getPermissions f) (\(SomeException _) -> return False)
+listCabalFiles :: FilePath -> IO [FilePath]
+listCabalFiles dir = map (dir </>) . Prelude.filter isCabalFile <$> listFiles dir
+
+isCabalFile :: FilePath -> Bool
+isCabalFile file = case splitExtension file of
+    (name, ".cabal") -> not (null name)
+    _ -> False
+
+listFiles :: FilePath -> IO [FilePath]
+listFiles dir = getDirectoryContents dir >>= filterM (doesFileExist . (dir </>))
+
+-- | Determine whether or not the file found at the provided filepath is executable.
+isExecutable :: FilePath -> IO Bool
+isExecutable f = E.catch (executable <$> getPermissions f) (\(SomeException _) -> return False)
 
 -- | Should we recompile xmonad configuration? Is it newer than the compiled
 -- binary?
@@ -642,12 +691,15 @@ shouldCompile dirs CompileGhc = do
         cs <- prep <$> E.catch (getDirectoryContents t) (\(SomeException _) -> return [])
         ds <- filterM doesDirectoryExist cs
         concat . ((cs \\ ds):) <$> mapM allFiles ds
+shouldCompile _ CompileCabal = return True
 shouldCompile dirs CompileStackGhc{} = do
     stackYamlT <- getModTime (stackYamlFileName dirs)
     binT <- getModTime (binFileName dirs)
     if binT < stackYamlT
         then True <$ 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."
 
@@ -659,17 +711,31 @@ compile :: Directories -> Compile -> IO ExitCode
 compile dirs method =
     bracket_ uninstallSignalHandlers installSignalHandlers $
         withFile (errFileName dirs) WriteMode $ \err -> do
-            let run = runProc (cfgDir dirs) err
+            let run = runProc err
             case method of
                 CompileGhc -> do
                     ghc <- fromMaybe "ghc" <$> lookupEnv "XMONAD_GHC"
                     run ghc ghcArgs
+                CompileCabal -> run "cabal" ["build"] .&&. copyBinary
+                  where
+                    copyBinary :: IO ExitCode
+                    copyBinary = readProc err "cabal" ["-v0", "list-bin", "."] >>= \ case
+                        Left status -> return status
+                        Right (trim -> path) -> copyBinaryFrom path
                 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
+    cwd :: FilePath
+    cwd = cfgDir dirs
+
+    ghcArgs :: [String]
     ghcArgs = [ "--make"
               , "xmonad.hs"
               , "-i" -- only look in @lib@
@@ -681,13 +747,51 @@ compile dirs method =
               , "-o", binFileName dirs
               ]
 
+    andCopyFromResultDir :: ExitCode -> IO ExitCode
+    andCopyFromResultDir exitCode = do
+      if exitCode == ExitSuccess then copyFromResultDir else return exitCode
+
+    findM :: (Monad m, Foldable t) => (a -> m Bool) -> t a -> m (Maybe a)
+    findM p = foldr (\x -> ifM (p x) (pure $ Just x)) (pure Nothing)
+
+    catchAny :: IO a -> (SomeException -> IO a) -> IO a
+    catchAny = E.catch
+
+    copyFromResultDir :: IO ExitCode
+    copyFromResultDir = do
+      let binaryDirectory = cfgDir dirs </> "result" </> "bin"
+      binFiles <- map (binaryDirectory </>) <$> catchAny (listDirectory binaryDirectory) (\_ -> return [])
+      mfilepath <- findM isExecutable binFiles
+      case mfilepath of
+        Just filepath -> copyBinaryFrom filepath
+        Nothing -> return $ ExitFailure 1
+
+    copyBinaryFrom :: FilePath -> IO ExitCode
+    copyBinaryFrom filepath = copyFile filepath (binFileName dirs) >> return ExitSuccess
+
     -- 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 }
+    runProc :: Handle -> String -> [String] -> IO ExitCode
+    runProc err exe args = do
+        (Nothing, Nothing, Nothing, h) <- createProcess_ "runProc" =<< mkProc err exe args
         waitForProcess h
 
+    readProc :: Handle -> String -> [String] -> IO (Either ExitCode String)
+    readProc err exe args = do
+        spec <- mkProc err exe args
+        (Nothing, Just out, Nothing, h) <- createProcess_ "readProc" spec{ std_out = CreatePipe }
+        result <- hGetContents out
+        hPutStr err result >> hFlush err
+        waitForProcess h >>= \ case
+            ExitSuccess -> return $ Right result
+            status -> return $ Left status
+
+    mkProc :: Handle -> FilePath -> [FilePath] -> IO CreateProcess
+    mkProc err exe args = do
+        hPutStrLn err $ unwords $ "$" : exe : args
+        hFlush err
+        return (proc exe args){ cwd = Just cwd, std_err = UseHandle err }
+
+    (.&&.) :: Monad m => m ExitCode -> m ExitCode -> m ExitCode
     cmd1 .&&. cmd2 = cmd1 >>= \case
         ExitSuccess -> cmd2
         e -> pure e
@@ -787,3 +891,6 @@ uninstallSignalHandlers = io $ do
     installHandler openEndedPipe Default Nothing
     installHandler sigCHLD Default Nothing
     return ()
+
+trim :: String -> String
+trim = reverse . dropWhile isSpace . reverse . dropWhile isSpace

src/XMonad/Layout.hs

@@ -62,9 +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)

src/XMonad/Main.hs

@@ -15,19 +15,18 @@
 --
 -----------------------------------------------------------------------------
 
-module XMonad.Main (xmonad, launch) where
+module XMonad.Main (xmonad, buildLaunch, launch) where
 
 import System.Locale.SetLocale
 import qualified Control.Exception as E
 import Data.Bits
 import Data.List ((\\))
 import Data.Foldable (traverse_)
-import Data.Function
 import qualified Data.Map as M
 import qualified Data.Set as S
 import Control.Monad.Reader
 import Control.Monad.State
-import Control.Monad (filterM, guard, unless, void, when)
+import Control.Monad (filterM, guard, unless, void, when, forever)
 import Data.Maybe (fromMaybe, isJust)
 import Data.Monoid (getAll)
 
@@ -132,25 +131,6 @@ buildLaunch dirs = do
       args <- getArgs
       executeFile bin 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 []
-        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
-
 -- | Entry point into xmonad for custom builds.
 --
 -- This function isn't meant to be called by the typical xmonad user
@@ -268,11 +248,10 @@ launch initxmc drs = do
             userCode $ startupHook initxmc
 
             rrData <- io $ xrrQueryExtension dpy
+            let rrUpdate = when (isJust rrData) . void . xrrUpdateConfiguration
 
             -- main loop, for all you HOF/recursion fans out there.
-            -- 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
+            forever $ prehandle =<< io (nextEvent dpy e >> rrUpdate e >> getEvent e)
 
     return ()
       where
@@ -283,8 +262,6 @@ launch initxmc drs = 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
@@ -485,36 +462,3 @@ grabButtons = do
     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

src/XMonad/ManageHook.hs

@@ -64,11 +64,8 @@ x <&&> y = ifM x y (pure False)
 (<||>) :: Monad m => m Bool -> m Bool -> m Bool
 x <||> y = ifM x (pure True) y
 
--- | 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
-
--- | Return the window title.
+-- | Return the window title; i.e., the string returned by @_NET_WM_NAME@,
+-- or failing that, the string returned by @WM_NAME@.
 title :: Query String
 title = ask >>= \w -> liftX $ do
     d <- asks display
@@ -77,7 +74,7 @@ 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; i.e., the /first/ string returned by
@@ -95,7 +92,9 @@ 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.
+-- identified by name. Works for ASCII strings only. For the properties
+-- @_NET_WM_NAME@/@WM_NAME@ and @WM_CLASS@ the specialised variants 'title'
+-- and 'appName'/'className' are preferred.
 stringProperty :: String -> Query String
 stringProperty p = ask >>= (\w -> liftX $ withDisplay $ \d -> fromMaybe "" <$> getStringProperty d w p)
 

src/XMonad/Operations.hs

@@ -33,10 +33,11 @@ module XMonad.Operations (
     -- * Keyboard and Mouse
     cleanMask, extraModifiers,
     mouseDrag, mouseMoveWindow, mouseResizeWindow,
-    setButtonGrab, setFocusX, cacheNumlockMask, mkGrabs,
+    setButtonGrab, setFocusX, cacheNumlockMask, mkGrabs, unGrab,
 
     -- * Messages
     sendMessage, broadcastMessage, sendMessageWithNoRefresh,
+    sendRestart, sendReplace,
 
     -- * Save and Restore State
     StateFile (..), writeStateToFile, readStateFile, restart,
@@ -196,6 +197,7 @@ windows f = do
         let m   = W.floating ws
             flt = [(fw, scaleRationalRect viewrect r)
                     | fw <- filter (`M.member` m) (W.index this)
+                    , fw `notElem` vis
                     , Just r <- [M.lookup fw m]]
             vs = flt ++ rs
 
@@ -473,6 +475,28 @@ mkGrabs ks = withDisplay $ \dpy -> do
          , 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
 
@@ -519,6 +543,59 @@ setLayout l = do
     handleMessage (W.layout ws) (SomeMessage ReleaseResources)
     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
 
@@ -649,6 +726,7 @@ floatLocation w =
 
   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
           point_sc <- pointScreen (fi $ wa_x wa) (fi $ wa_y wa)
@@ -663,13 +741,14 @@ floatLocation w =
               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  = fi (wa_width  wa + bw*2) % fi (rect_width sr)
-              height = fi (wa_height wa + bw*2) % 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 width height
-                  else W.RationalRect (0.5 - width/2) (0.5 - height/2) width height
+                  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)
 

src/XMonad/StackSet.hs

@@ -106,7 +106,10 @@ import qualified Data.Map  as M (Map,insert,delete,empty)
 --
 --      <https://dspace.library.uu.nl/handle/1874/2532 R. Hinze and J. Jeuring, Functional Pearl: Weaving a Web>
 --
--- and Conor McBride's zipper differentiation paper.
+-- 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

stack.yaml

@@ -1,4 +1,4 @@
-resolver: lts-19.6
+resolver: lts-21.12
 
 packages:
 - ./

tests/Properties.hs

@@ -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)

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
 
 ------------------------------------------------------------------------
@@ -27,6 +28,22 @@ 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) ==>
@@ -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)
       &&

xmonad.cabal

@@ -1,5 +1,5 @@
 name:               xmonad
-version:            0.17.2
+version:            0.18.0.9
 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
@@ -27,7 +27,7 @@ author:             Spencer Janssen, Don Stewart, Adam Vogt, David Roundy, Jason
                     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 == 8.6.5 || == 8.8.4 || == 8.10.7 || == 9.0.2 || == 9.2.7 || == 9.4.4 || == 9.6.1
+tested-with:        GHC == 8.6.5 || == 8.8.4 || == 8.10.7 || == 9.0.2 || == 9.2.8 || == 9.4.8 || == 9.6.7 || == 9.8.4 || == 9.10.2 || == 9.12.2
 category:           System
 homepage:           http://xmonad.org
 bug-reports:        https://github.com/xmonad/xmonad/issues
@@ -65,7 +65,7 @@ library
                    XMonad.StackSet
   other-modules:   Paths_xmonad
   hs-source-dirs:  src
-  build-depends:   base                  >= 4.11 && < 5
+  build-depends:   base                  >= 4.12 && < 5
                  , X11                   >= 1.10 && < 1.11
                  , containers
                  , data-default-class
@@ -129,5 +129,8 @@ test-suite properties
                 , xmonad
   default-language: Haskell2010
 
+  if impl(ghc > 9.8)
+    ghc-options:   -Wno-x-partial
+
   if flag(pedantic)
     ghc-options:   -Werror