Moving to Doom Emacs!

.emacs.d/modules/lang/haskell/+intero.el

@@ -0,0 +1,30 @@
+;;; lang/haskell/+intero.el -*- lexical-binding: t; -*-
+;;;###if (featurep! +intero)
+
+(use-package! intero
+  :commands intero-mode
+  :init
+  (add-hook! 'haskell-mode-local-vars-hook
+    (defun +haskell-init-intero-h ()
+      "Initializes `intero-mode' in haskell-mode, unless stack isn't installed.
+This is necessary because `intero-mode' doesn't do its own error checks."
+      (when (derived-mode-p 'haskell-mode)
+        (if (executable-find "stack")
+            (intero-mode +1)
+          (message "Couldn't find stack. Refusing to enable intero-mode.")))))
+  :config
+  (setq haskell-compile-cabal-build-command "stack build --fast")
+  (set-lookup-handlers! 'intero-mode :definition #'intero-goto-definition)
+  (set-company-backend! 'intero-mode 'intero-company)
+  (when (featurep! :tools flycheck)
+    (flycheck-add-next-checker 'intero '(warning . haskell-hlint)))
+
+  (when (featurep 'evil)
+    (add-hook 'intero-mode-hook #'evil-normalize-keymaps))
+  (map! :localleader
+        :map intero-mode-map
+        "t" #'intero-type-at
+        "i" #'intero-info
+        "l" #'intero-repl-load
+        "e" #'intero-repl-eval-region
+        "a" #'intero-apply-suggestions))