lang/haskell: refactor + add company-ghc

modules/lang/haskell/config.el

@@ -1,18 +1,16 @@
 ;;; module-haskell.el
 
-;; requires cabal (flycheck), ghci/hugs (repl)
-
 (def-package! haskell-mode
-  :mode (("\\.hs$" . haskell-mode)
+  :mode "\\.hs$"
-         ("\\.ghci$" . ghci-script-mode)
+  :mode ("\\.ghci$" . ghci-script-mode)
-         ("\\.cabal$" . haskell-cabal-mode))
+  :mode ("\\.cabal$" . haskell-cabal-mode)
   :interpreter (("runghc" . haskell-mode)
                 ("runhaskell" . haskell-mode))
   :config
   (load "haskell-mode-autoloads" nil t)
 
-  (set! :popup "*debug:haskell*" :size 20)
   (set! :repl 'haskell-mode #'switch-to-haskell)
+
   (push ".hi" completion-ignored-extensions)
 
   (autoload 'switch-to-haskell "inf-haskell" nil t)
@@ -23,7 +21,18 @@
 (def-package! dante
   :after haskell-mode
   :config
-  (when (executable-find "cabal")
+  (if (executable-find "cabal")
     (add-hook! 'haskell-mode-hook
-      #'(flycheck-mode dante-mode interactive-haskell-mode))))
+      #'(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
+  :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")))

modules/lang/haskell/packages.el

@@ -1,7 +1,8 @@
 ;; -*- no-byte-compile: t; -*-
 ;;; lang/haskell/packages.el
 
-;; requires haskell cabal-install ghz happy alex
-
 (package! haskell-mode)
 (package! dante)
+
+(when (featurep! :completion company)
+  (package! company-ghc))