haskell-goto-{prev,next}-error: steal from ghc-mod

Author: deepfire

haskell-load.el

@@ -294,10 +294,33 @@ actual Emacs buffer of the module being loaded."
 (defvar haskell-check-warning-fringe (propertize "?" 'display '(left-fringe question-mark)))
 (defvar haskell-check-hole-fringe    (propertize "_" 'display '(left-fringe horizontal-bar)))
 
+(defun haskell-check-overlay-p (ovl)
+  (overlay-get ovl 'haskell-check))
+
 (defun haskell-check-remove-overlays (buffer)
   (with-current-buffer buffer
     (remove-overlays (point-min) (point-max) 'haskell-check t)))
 
+(defun haskell-goto-prev-error ()
+  (interactive)
+  (let* ((here (point))
+         (ovls0 (remove-if-not 'haskell-check-overlay-p (overlays-at here)))
+         (end (if ovls0 (overlay-start (car ovls0)) here))
+         (ovls1 (overlays-in (point-min) end))
+         (ovls2 (remove-if-not 'haskell-check-overlay-p ovls1))
+         (pnts (mapcar 'overlay-start ovls2)))
+    (if pnts (goto-char (apply 'max pnts)))))
+
+(defun haskell-goto-next-error ()
+  (interactive)
+  (let* ((here (point))
+         (ovls0 (remove-if-not 'haskell-check-overlay-p (overlays-at here)))
+         (beg (if ovls0 (overlay-end (car ovls0)) here))
+         (ovls1 (overlays-in beg (point-max)))
+         (ovls2 (remove-if-not 'haskell-check-overlay-p ovls1))
+         (pnts (mapcar 'overlay-start ovls2)))
+    (if pnts (goto-char (apply 'min pnts)))))
+
 (defun haskell-check-paint-overlay (buffer error-from-this-file-p line msg file err hole coln)
   (with-current-buffer buffer
     (let (beg end)