ipe: migrate to by-name

ipe: refactor package definitions

ghostscript: migrate to by-name

pkgs/applications/graphics/ipe/default.nix pkgs/by-name/ip/ipe/package.nix

···
   copyDesktopItems,
   cairo,
   freetype,
-  ghostscript,
+  ghostscriptX,
   gsl,
   libjpeg,
   libpng,
   libspiro,
   lua5,
-  qtbase,
-  qtsvg,
+  qt6Packages,
   texliveSmall,
   qhull,
-  wrapQtAppsHook,
   zlib,
   withTeXLive ? true,
   withQVoronoi ? false,
   buildPackages,
 }:
 
-stdenv.mkDerivation rec {
+stdenv.mkDerivation (finalAttrs: {
   pname = "ipe";
   version = "7.2.30";
 
   src = fetchFromGitHub {
     owner = "otfried";
     repo = "ipe";
-    tag = "v${version}";
+    tag = "v${finalAttrs.version}";
     hash = "sha256-bvwEgEP/cinigixJr8e964sm6secSK+7Ul7WFfwM0gE=";
   };
 
   nativeBuildInputs = [
     pkg-config
     copyDesktopItems
-    wrapQtAppsHook
+    qt6Packages.wrapQtAppsHook
   ];
 
   buildInputs = [
     cairo
     freetype
-    ghostscript
+    ghostscriptX
     gsl
     libjpeg
     libpng
     libspiro
     lua5
+  ]
+  ++ (with qt6Packages; [
     qtbase
     qtsvg
     zlib
-  ]
+  ])
   ++ (lib.optionals withTeXLive [
     texliveSmall
   ])
···
 
   desktopItems = [
     (makeDesktopItem {
-      name = pname;
+      name = "ipe";
       desktopName = "Ipe";
       genericName = "Drawing editor";
       comment = "A drawing editor for creating figures in PDF format";
···
 
   postInstall = ''
     mkdir -p $out/share/icons/hicolor/128x128/apps
-    ln -s $out/share/ipe/${version}/icons/icon_128x128.png $out/share/icons/hicolor/128x128/apps/ipe.png
+    ln -s $out/share/ipe/${finalAttrs.version}/icons/icon_128x128.png $out/share/icons/hicolor/128x128/apps/ipe.png
   '';
 
-  meta = with lib; {
+  meta = {
     description = "Editor for drawing figures";
     homepage = "http://ipe.otfried.org"; # https not available
-    license = licenses.gpl3Plus;
+    license = lib.licenses.gpl3Plus;
     longDescription = ''
       Ipe is an extensible drawing editor for creating figures in PDF and Postscript format.
       It supports making small figures for inclusion into LaTeX-documents
       as well as presentations in PDF.
     '';
-    maintainers = with maintainers; [ ttuegel ];
-    platforms = platforms.linux;
+    maintainers = with lib.maintainers; [ ttuegel ];
+    platforms = lib.platforms.linux;
   };
-}
+})

pkgs/by-name/gh/ghostscriptX/package.nix

···
+{
+  ghostscript,
+}:
+
+ghostscript.override {
+  cupsSupport = true;
+  x11Support = true;
+}

pkgs/by-name/gh/ghostscript_headless/package.nix

···
+{
+  ghostscript,
+}:
+
+ghostscript.override {
+  cupsSupport = false;
+  x11Support = false;
+}

pkgs/top-level/all-packages.nix

···
     lua = lua5_1;
   };
 
-  ipe = qt6Packages.callPackage ../applications/graphics/ipe {
-    ghostscript = ghostscriptX;
-    lua5 = lua5_3;
-  };
-
   ir.lv2 = callPackage ../applications/audio/ir.lv2 { };
 
   jabcode = callPackage ../development/libraries/jabcode { };
···
   gajim = callPackage ../applications/networking/instant-messengers/gajim {
     inherit (gst_all_1) gstreamer gst-plugins-base gst-libav;
     gst-plugins-good = gst_all_1.gst-plugins-good.override { gtkSupport = true; };
-  };
-
-  ghostscriptX = ghostscript.override {
-    cupsSupport = true;
-    x11Support = true;
-  };
-
-  ghostscript_headless = ghostscript.override {
-    cupsSupport = false;
-    x11Support = false;
   };
 
   gnuk = callPackage ../misc/gnuk {