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

ci: Regenerate haskell-ci

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

@@ -38,13 +38,13 @@ set in GitHub repository secrets.
    linux:
      name: Haskell-CI - Linux - ${{ matrix.compiler }}
 @@ -33,6 +40,7 @@
-             compilerVersion: 9.8.1
+             compilerVersion: 9.8.4
              setup-method: ghcup
              allow-failure: false
 +            upload: true
-           - compiler: ghc-9.6.4
+           - compiler: ghc-9.6.7
              compilerKind: ghc
-             compilerVersion: 9.6.4
+             compilerVersion: 9.6.7
 @@ -257,6 +265,10 @@
        - name: haddock
          run: |
@@ -56,19 +56,24 @@ set in GitHub repository secrets.
        - name: unconstrained build
          run: |
            rm -f cabal.project.local
-@@ -267,3 +279,75 @@
+@@ -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: 0.17.20240109
+# version: 0.19.20250506
 #
-# REGENDATA ("0.17.20240109",["github","cabal.project"])
+# REGENDATA ("0.19.20250506",["github","cabal.project"])
 #
 name: Haskell-CI
 on:
@@ -26,24 +26,34 @@ 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: ${{ matrix.allow-failure }}
     strategy:
       matrix:
         include:
-          - compiler: ghc-9.8.1
+          - compiler: ghc-9.12.2
             compilerKind: ghc
-            compilerVersion: 9.8.1
+            compilerVersion: 9.12.2
+            setup-method: ghcup
+            allow-failure: false
+          - compiler: ghc-9.10.2
+            compilerKind: ghc
+            compilerVersion: 9.10.2
+            setup-method: ghcup
+            allow-failure: false
+          - compiler: ghc-9.8.4
+            compilerKind: ghc
+            compilerVersion: 9.8.4
             setup-method: ghcup
             allow-failure: false
             upload: true
-          - compiler: ghc-9.6.4
+          - compiler: ghc-9.6.7
             compilerKind: ghc
-            compilerVersion: 9.6.4
+            compilerVersion: 9.6.7
             setup-method: ghcup
             allow-failure: false
           - compiler: ghc-9.4.8
@@ -69,36 +79,39 @@ jobs:
           - compiler: ghc-8.8.4
             compilerKind: ghc
             compilerVersion: 8.8.4
-            setup-method: hvr-ppa
+            setup-method: ghcup
             allow-failure: false
           - compiler: ghc-8.6.5
             compilerKind: ghc
             compilerVersion: 8.6.5
-            setup-method: hvr-ppa
+            setup-method: ghcup
             allow-failure: false
       fail-fast: false
     steps:
-      - name: apt
+      - name: apt-get install
         run: |
           apt-get update
           apt-get install -y --no-install-recommends gnupg ca-certificates dirmngr curl git software-properties-common libtinfo5
-          if [ "${{ matrix.setup-method }}" = ghcup ]; then
-            mkdir -p "$HOME/.ghcup/bin"
-            curl -sL https://downloads.haskell.org/ghcup/0.1.20.0/x86_64-linux-ghcup-0.1.20.0 > "$HOME/.ghcup/bin/ghcup"
-            chmod a+x "$HOME/.ghcup/bin/ghcup"
-            "$HOME/.ghcup/bin/ghcup" install ghc "$HCVER" || (cat "$HOME"/.ghcup/logs/*.* && false)
-            "$HOME/.ghcup/bin/ghcup" install cabal 3.10.2.0 || (cat "$HOME"/.ghcup/logs/*.* && false)
-            apt-get update
-            apt-get install -y libx11-dev libxext-dev libxinerama-dev libxrandr-dev libxss-dev
-          else
-            apt-add-repository -y 'ppa:hvr/ghc'
-            apt-get update
-            apt-get install -y "$HCNAME" libx11-dev libxext-dev libxinerama-dev libxrandr-dev libxss-dev
-            mkdir -p "$HOME/.ghcup/bin"
-            curl -sL https://downloads.haskell.org/ghcup/0.1.20.0/x86_64-linux-ghcup-0.1.20.0 > "$HOME/.ghcup/bin/ghcup"
-            chmod a+x "$HOME/.ghcup/bin/ghcup"
-            "$HOME/.ghcup/bin/ghcup" install cabal 3.10.2.0 || (cat "$HOME"/.ghcup/logs/*.* && false)
-          fi
+          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: ${{ matrix.compiler }}
@@ -109,30 +122,12 @@ jobs:
           echo "LANG=C.UTF-8" >> "$GITHUB_ENV"
           echo "CABAL_DIR=$HOME/.cabal" >> "$GITHUB_ENV"
           echo "CABAL_CONFIG=$HOME/.cabal/config" >> "$GITHUB_ENV"
-          HCDIR=/opt/$HCKIND/$HCVER
-          if [ "${{ matrix.setup-method }}" = ghcup ]; then
-            HC=$("$HOME/.ghcup/bin/ghcup" whereis ghc "$HCVER")
-            HCPKG=$(echo "$HC" | sed 's#ghc$#ghc-pkg#')
-            HADDOCK=$(echo "$HC" | sed 's#ghc$#haddock#')
-            echo "HC=$HC" >> "$GITHUB_ENV"
-            echo "HCPKG=$HCPKG" >> "$GITHUB_ENV"
-            echo "HADDOCK=$HADDOCK" >> "$GITHUB_ENV"
-            echo "CABAL=$HOME/.ghcup/bin/cabal-3.10.2.0 -vnormal+nowrap" >> "$GITHUB_ENV"
-          else
-            HC=$HCDIR/bin/$HCKIND
-            echo "HC=$HC" >> "$GITHUB_ENV"
-            echo "HCPKG=$HCDIR/bin/$HCKIND-pkg" >> "$GITHUB_ENV"
-            echo "HADDOCK=$HCDIR/bin/haddock" >> "$GITHUB_ENV"
-            echo "CABAL=$HOME/.ghcup/bin/cabal-3.10.2.0 -vnormal+nowrap" >> "$GITHUB_ENV"
-          fi
-
           HCNUMVER=$(${HC} --numeric-version|perl -ne '/^(\d+)\.(\d+)\.(\d+)(\.(\d+))?$/; print(10000 * $1 + 100 * $2 + ($3 == 0 ? $5 != 1 : $3))')
           echo "HCNUMVER=$HCNUMVER" >> "$GITHUB_ENV"
           echo "ARG_TESTS=--enable-tests" >> "$GITHUB_ENV"
           echo "ARG_BENCH=--enable-benchmarks" >> "$GITHUB_ENV"
           echo "HEADHACKAGE=false" >> "$GITHUB_ENV"
           echo "ARG_COMPILER=--$HCKIND --with-compiler=$HC" >> "$GITHUB_ENV"
-          echo "GHCJSARITH=0" >> "$GITHUB_ENV"
         env:
           HCKIND: ${{ matrix.compilerKind }}
           HCNAME: ${{ matrix.compiler }}
@@ -182,7 +177,7 @@ jobs:
           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
@@ -214,7 +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
@@ -222,7 +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
@@ -256,20 +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/nix.yml

@@ -6,19 +6,15 @@ 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@v25
+        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@v4
       - name: Build

.github/workflows/packdeps.yml

@@ -40,10 +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

@@ -18,6 +18,8 @@ jobs:
           - 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

.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 +1,27 @@
 # 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

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
@@ -113,6 +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
 ```
 
@@ -1066,6 +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

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
@@ -46,7 +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.
@@ -54,7 +54,7 @@
             };
             compiler = mkOption {
               default = null;
-              type = nullOr string;
+              type = nullOr str;
               example = literalExpression "\"ghc922\"";
               description = ''
                 Which compiler to build xmonad with.

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

@@ -8,6 +8,7 @@
 {-# LANGUAGE NamedFieldPuns #-}
 {-# LANGUAGE ScopedTypeVariables #-}
 {-# LANGUAGE DerivingVia #-}
+{-# LANGUAGE ViewPatterns #-}
 
 -----------------------------------------------------------------------------
 -- |
@@ -50,6 +51,7 @@ import Control.Monad.Fix (fix)
 import Control.Monad.State
 import Control.Monad.Reader
 import Control.Monad (filterM, guard, void, when)
+import Data.Char (isSpace)
 import Data.Semigroup
 import Data.Traversable (for)
 import Data.Time.Clock (UTCTime)
@@ -589,6 +591,7 @@ nixDefaultFileName  Directories{ cfgDir } = cfgDir </> "default.nix"
 -- | Compilation method for xmonad configuration.
 data Compile
   = CompileGhc
+  | CompileCabal
   | CompileStackGhc FilePath
   | CompileNixFlake
   | CompileNixDefault
@@ -599,7 +602,7 @@ data Compile
 -- configuration directory.
 detectCompile :: Directories -> IO Compile
 detectCompile dirs =
-  tryScript <|> tryStack <|> tryNixFlake <|> tryNixDefault <|> useGhc
+  tryScript <|> tryStack <|> tryNixFlake <|> tryNixDefault <|> tryCabal <|> useGhc
   where
     buildScript = buildScriptFileName dirs
     stackYaml = stackYamlFileName dirs
@@ -636,6 +639,16 @@ detectCompile dirs =
         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 none of "
                 <> intercalate ", "
@@ -643,9 +656,20 @@ detectCompile dirs =
                      , show stackYaml
                      , show flakeNix
                      , show defaultNix
-                     ] <> " exist."
+                     ] <> " nor a suitable .cabal file exist."
         pure CompileGhc
 
+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)
@@ -667,6 +691,7 @@ 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)
@@ -686,11 +711,17 @@ 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)
@@ -701,6 +732,10 @@ compile dirs method =
                 CompileScript script ->
                     run script [binFileName dirs]
   where
+    cwd :: FilePath
+    cwd = cfgDir dirs
+
+    ghcArgs :: [String]
     ghcArgs = [ "--make"
               , "xmonad.hs"
               , "-i" -- only look in @lib@
@@ -711,26 +746,52 @@ compile dirs method =
               , "-outputdir", buildDirName dirs
               , "-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 -> copyFile filepath (binFileName dirs) >> return ExitSuccess
+        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
@@ -830,3 +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/Main.hs

@@ -26,7 +26,7 @@ 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)
 
@@ -248,11 +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
@@ -263,8 +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

src/XMonad/ManageHook.hs

@@ -64,7 +64,8 @@ x <&&> y = ifM x y (pure False)
 (<||>) :: Monad m => m Bool -> m Bool -> m Bool
 x <||> y = ifM x (pure True) y
 
--- | 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
@@ -91,7 +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)
 

xmonad.cabal

@@ -1,5 +1,5 @@
 name:               xmonad
-version:            0.18.0
+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 || == 9.2.8 || == 9.4.8 || == 9.6.4 || == 9.8.1
+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