fix(haskell): Fix ghc[i]-with-packages

- Export functions.
- Simplify arg-parsing by using getopts instead of getopt.

modules/home/users/crumb/haskell.nix

@@ -11,36 +11,45 @@ in {
     programs.bash.profileExtra = ''
       # Start a GHCi REPL with the given packages made available.
       ghci-with-packages () {
-        nix-shell -p "haskellPackages.ghcWithPackages (p: with p; [ $@ ])" \
-          --run ghci
-      }
-
-      # Run GHC with the given packages made available.
-      ghc-with-packages () {
-        getopt -o "p" -- "$@"
-        while true; do
-          case "$1" in
-            -p)
-              packages="$1"
-              shift 2
+        packages=""
+        while getopts 'p:h' opt; do
+          case "$opt" in
+            p)
+              packages="''${OPTARG}"
               ;;
-            --)
-              shift
-              break
+            ?|h)
+              echo >&2 "Usage: $(basename $0) [-p packages] [-- ghci-options]"
+              exit 1
               ;;
           esac
         done
+        shift "$(($OPTIND -1))"
 
-        if [ $? -ne 0 ]; then
-         echo "Invalid options provided"
-         exit 1
-        fi
+        nix-shell -p "haskellPackages.ghcWithPackages (p: with p; [ $packages ])" \
+          --run "ghci $@"
+      }
+      export -f ghci-with-packages
 
-        eval set -- "$options"
+      # Run GHC with the given packages made available.
+      ghc-with-packages () {
+        packages=""
+        while getopts 'p:h' opt; do
+          case "$opt" in
+            p)
+              packages="''${OPTARG}"
+              ;;
+            ?|h)
+              echo >&2 "Usage: $(basename $0) [-p packages] [-- ghc-options]"
+              exit 1
+              ;;
+          esac
+        done
+        shift "$(($OPTIND -1))"
 
         nix-shell -p "haskellPackages.ghcWithPackages (p: with p; [ $packages ])" \
           --run "ghc $@"
       }
+      export -f ghc-with-packages
     '';
 
     sydnix.impermanence.cache.directories =