lang/haskell: add intero support #158

To use dante instead, change `haskell` to `(haskell +dante)` in
~/.emacs.d/init.el.

modules/lang/haskell/+dante.el

@@ -0,0 +1,13 @@
+;;; lang/haskell/+dante.el -*- lexical-binding: t; -*-
+
+(def-package! dante
+  :after haskell-mode
+  :init
+  (add-hook! 'haskell-mode-hook #'(dante-mode interactive-haskell-mode))
+  :config
+  (unless (executable-find "cabal")
+    (warn "haskell-mode: couldn't find cabal")
+    (remove-hook 'haskell-mode-hook #'dante-mode))
+
+    (add-hook 'dante-mode-hook #'flycheck-mode))
+

modules/lang/haskell/+intero.el

@@ -0,0 +1,21 @@
+;;; lang/haskell/+intero.el -*- lexical-binding: t; -*-
+
+(def-package! intero
+  :commands intero-mode
+  :init
+  (add-hook 'haskell-mode-hook #'intero-mode)
+  :config
+  (unless (executable-find "stack")
+    (warn "haskell-mode: couldn't find stack, disabling intero")
+    (remove-hook 'haskell-mode-hook #'intero-mode))
+
+  (add-hook! 'intero-mode-hook #'(flycheck-mode eldoc-mode))
+
+  (set! :popup "^intero:backend:" :regex t :size 12)
+  (set! :jump :definition #'intero-goto-definition))
+
+
+(def-package! hindent
+  :commands hindent-mode
+  :init
+  (add-hook 'haskell-mode-hook #'hindent-mode))

modules/lang/haskell/config.el

@@ -17,21 +17,21 @@
     (map! :map inf-haskell-mode-map "ESC ESC" #'doom/popup-close)))
 
 
-(def-package! dante
-  :after haskell-mode
-  :config
-  (if (executable-find "cabal")
-    (add-hook! 'haskell-mode-hook
-      #'(flycheck-mode dante-mode interactive-haskell-mode))
-    (warn "haskell-mode: couldn't find cabal")))
-
-
 (def-package! company-ghc
   :when (featurep! :completion company)
   :after haskell-mode
+  :init
+  (add-hook 'haskell-mode-hook #'ghc-comp-init)
   :config
-  (set! :company-backend 'haskell-mode #'company-ghc)
-  (setq company-ghc-show-info 'oneline)
   (if (executable-find "ghc-mod")
-      (add-hook 'haskell-mode-hook #'ghc-comp-init)
-    (warn "haskell-mode: couldn't find ghc-mode")))
+      (set! :company-backend 'haskell-mode #'company-ghc)
+    (warn "haskell-mode: couldn't find ghc-mode")
+    (remove-hook 'haskell-mode-hook #'ghc-comp-init))
+
+  (setq company-ghc-show-info 'oneline))
+
+
+;;
+(if (featurep! +dante)
+    (load! +dante)
+  (load! +intero))

modules/lang/haskell/packages.el

@@ -2,7 +2,13 @@
 ;;; lang/haskell/packages.el
 
 (package! haskell-mode)
-(package! dante)
-
 (when (featurep! :completion company)
   (package! company-ghc))
+
+;;
+(cond ((featurep! +dante)
+       (package! dante))
+      (t
+       (package! intero)
+       (package! hindent)))
+