 ;; Common code for case splitting and refinement
 
 (defun ghc-perform-rewriting (info)
+  "Replace code with new string obtained from ghc-mod"
   (let* ((current-line    (line-number-at-pos))
 	 (begin-line      (ghc-sinfo-get-beg-line info))
 	 (begin-line-diff (+ 1 (- begin-line current-line)))

(ghc-defstruct sinfo beg-line beg-column end-line end-column info)

(defun ghc-case-split ()
  (interactive)
  (let ((info (ghc-obtain-case-split)))
    (if (null info)

;;;

(defun ghc-refine ()
  "Refine a hole using a user-specified function"
  (interactive)
  (let ((info (ghc-obtain-refine (read-string "Refine with: "))))
    (if (null info)
