xmobar: write configuration in haskell

nix/configurations/vanadium/home/xmobar.nix

@@ -1,50 +1,26 @@
-{
+{pkgs, ...}: {
-  programs.xmobar = {
+  home.packages = let
-    enable = true;
+    wrapped-xmobar = pkgs.symlinkJoin {
-    # XMobar's config file is not a segment of valid Haskell source code -- it is instead a DSL
+      name = "xmobar";
-    # Note how `Run` handles its arguments properly without parens?
+      paths = with pkgs; [
-    #
+        # Xmobar wants ghc
-    # Also xmobar wants GHC if we use it as a library, and I'm lazy, you probably want to keep it this way.
+        (haskellPackages.ghcWithPackages (self: [
-    extraConfig = ''
+          self.xmobar
-      Config { overrideRedirect = False
+        ]))
-             , font             = "Iosevka 13"
+        # The executable
-             , bgColor          = "#000000"
+        xmobar
-             , fgColor          = "#FFFFFF"
+      ];
-             , position = BottomH 30
+    };
-             , commands = [ Run Date "%a %d %H:%M:%S" "date" 10
+  in [
-                          , Run Com "tomorrow"
+    wrapped-xmobar
-                              [ "--target", "2025-08-14"
+  ];
-                              , "--target", "2025-08-21"
+
-                              ] "" 3600
+  xdg.configFile = {
-                          , Run Battery
+    "xmobar" = {
-                              [ "-t", "<left> (<timeleft>"
+      # Xmobar uses the directory to compile too,
-                              , "-H", "70"
+      # Linking the entire folder directly would make the directory not writable
-                              , "-L", "20"
+      recursive = true;
-                              , "-h", "green"
+      source = "${./xmobar}";
-                              , "-n", "orange"
+    };
-                              , "-l", "red"
-                              , "--"
-                              , "-P"
-                              , "-A", "20"
-                              , "-a", "notify-send -u critical \"Battery Low\" \"Please charge your battery\""
-                              ]
-                              60
-                          , Run Com "powerprofilesctl" [ "get" ] "" 60
-                          , Run XMonadLog
-                          , Run
-                              Weather "LFRN"
-                              [ "-t", "<station>: <tempC>C"
-                              , "-L","10", "-H", "25"
-                              , "--normal", "white"
-                              , "--high", "orange"
-                              , "--low", "blue"
-                              ]
-                              9000
-                          ]
-             , sepChar  = "%"
-             , alignSep = "}{"
-             , template = " %XMonadLog% }{ %LFRN% | %battery%, %powerprofilesctl%) | %date%, j%tomorrow% "
-             }
-    '';
   };
 }

nix/configurations/vanadium/home/xmobar/xmobar.hs

@@ -0,0 +1,61 @@
+import Xmobar
+
+import Data.Function ((&))
+
+config =
+  defaultConfig
+    { overrideRedirect = False
+    , font = "Iosevka 13"
+    , bgColor = "#000000"
+    , fgColor = "#FFFFFF"
+    , position = BottomH 30
+    , commands =
+        [ Run $ Date "%a %d %H:%M:%S" "date" (1 &second)
+        , Run $
+            Com
+              "tomorrow"
+              [ "--target", "2025-08-14"
+              , "--target", "2025-08-21"
+              ]
+              ""
+              (60 &minute)
+        , Run $
+            Battery
+              [ "-t", "<left> (<timeleft>"
+              , "-H", "70"
+              , "-L", "20"
+              , "-h", "green"
+              , "-n", "orange"
+              , "-l", "red"
+              , "--"
+              , "-P"
+              , "-A", "20"
+              , "-a", "notify-send -u critical \"Battery Low\" \"Please charge your battery\""
+              ]
+              (6 &second)
+        , Run $ Com "powerprofilesctl" ["get"] "" (6 &second)
+        , Run XMonadLog
+        , Run $
+            Weather
+              "LFRN"
+              [ "-t", "<station>: <tempC>C"
+              , "-L","10", "-H", "25"
+              , "--normal", "white"
+              , "--high", "orange"
+              , "--low", "blue"
+              ]
+              (15 &minute)
+        ]
+    , sepChar = "%"
+    , alignSep = "}{"
+    , template = " %XMonadLog% }{ %LFRN% | %battery%, %powerprofilesctl%) | %date%, j%tomorrow% "
+    }
+
+second :: Int -> Int
+second = (* 10)
+
+minute :: Int -> Int
+minute = (* 60) . second
+
+main :: IO ()
+main = xmobar config