[Emacs] Only enable lsp-haskell when hie binary exists

dotfiles/config/xmonad/build

@@ -1,9 +1,36 @@
 #!/usr/bin/env bash
 
+function min {
+	[ $1 -le $2 ] && echo "$1" || echo "$2"
+}
+
+function get_exe_dir {
+	# XXX: This exists because calling in to stack is kind of slow with nix
+	# integration enabled, even when just using it to get a path.
+	if [ -e ./.cached-stack-install-path ]; then
+		cat .cached-stack-install-path
+	else
+		stack path --local-install-root
+	fi
+}
+
+function do_rebuild {
+
+}
+
 SRC_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
 
 EXE_NAME=imalison-xmonad
+EXE_LOCATION=$(get_exe_dir)/bin/$EXE_NAME
 output_file=$1; shift
 
-stack install
-cp -uf $(stack path --local-install-root)/bin/$EXE_NAME $output_file
+if [ -e ./.cached-stack-install-path ]; then
+	last_built=$(stat -c '%Y' $EXE_LOCATION)
+	xmonad_modified=$(stat -c '%Y' ./xmonad.hs)
+
+	[ $last_built -lt $xmonad_modified ] && stack install
+else
+	stack install
+fi
+
+cp -uf $EXE_LOCATION $output_file

dotfiles/config/xmonad/stack.yaml

@@ -9,3 +9,12 @@ packages:
 extra-deps:
 - X11-xft-0.3.1
 resolver: lts-11.7
+nix:
+  packages:
+    - pkgconfig
+    - x11
+    - xorg.libX11
+    - xorg.libXext
+    - xorg.libXinerama
+    - xorg.libXrandr
+    - xorg.libXrender

dotfiles/emacs.d/README.org

@@ -2774,7 +2774,8 @@ The following is taken from [[https://github.com/syl20bnr/spacemacs/blob/a650877
 #+BEGIN_SRC emacs-lisp
 (use-package lsp-haskell
   :config
-  (add-hook 'haskell-mode-hook 'lsp-haskell-enable))
+  (when (executable-find "hie")
+    (add-hook 'haskell-mode-hook 'lsp-haskell-enable)))
 #+END_SRC
 **** intero
 Intero seems to be causing hangs, so it has been disabled

dotfiles/lib/bin/xmonad

@@ -1,10 +0,0 @@
-#!/usr/bin/env zsh
-# -*- mode:sh
-
-if command_exists "imalison-taffybar"; then
-	imalison-xmonad "$@"
-else
-	# Move .lib/bin to the end of PATH so that this script is not called again
-	add_to_path "$HOME/.lib/bin" --after
-	xmonad "$@"
-fi