Merge pull request #1540 from haskell/haskell-string-utils

haskell-string-utils

Author: gracjan

haskell-interactive-mode.el

@@ -35,7 +35,7 @@
 (require 'haskell-font-lock)
 (require 'haskell-presentation-mode)
 (require 'haskell-utils)
-
+(require 'haskell-string)
 (require 'ansi-color)
 (require 'cl-lib)
 (require 'etags)

haskell-load.el

@@ -27,6 +27,7 @@
 (require 'haskell-modules)
 (require 'haskell-commands)
 (require 'haskell-session)
+(require 'haskell-string)
 
 (defun haskell-process-look-config-changes (session)
   "Check whether a cabal configuration file has changed.

haskell-mode.el

@@ -1198,19 +1198,6 @@ generated."
         (let ((tags-file-name dir))
           (xref-find-definitions and-then-find-this-tag))))))
 
-(defun haskell-mode-message-line (str)
-  "Echo STR in mini-buffer.
-Given string is shrinken to single line, multiple lines just
-disturbs the programmer."
-  (message "%s" (haskell-mode-one-line str (frame-width))))
-
-(defun haskell-mode-one-line (str width)
-  "Try to fit STR as much as possible on one line according to given WIDTH."
-  (let* ((long-line (replace-regexp-in-string "\n" " " str))
-         (condensed  (replace-regexp-in-string
-                      " +" " " (haskell-string-trim long-line))))
-    (truncate-string-to-width condensed width nil nil "…")))
-
 ;; Provide ourselves:
 (provide 'haskell-mode)
 ;;; haskell-mode.el ends here

haskell-string.el

@@ -27,6 +27,8 @@
 
 ;;; Code:
 
+(require 'cl-lib)
+
 (defun haskell-string-trim (string)
   "Remove whitespace around STRING.
 
@@ -162,6 +164,33 @@ See also `haskell-string-take'."
    ((< n 1) "")
    (t (concat (substring string 0 (1- n)) "…"))))
 
+(defun haskell-string-chomp (str)
+  "Chomp leading and tailing whitespace from STR."
+  (while (string-match "\\`\n+\\|^\\s-+\\|\\s-+$\\|\n+\\'"
+                       str)
+    (setq str (replace-match "" t t str)))
+  str)
+
+(defun haskell-string-split-to-lines (str)
+  "Split STR to lines and return a list of strings with preceeding and
+succeding space removed."
+  (when (stringp str)
+    (cl-mapcar #'haskell-string-chomp (split-string str "\n"))))
+
+(defun haskell-string-trim-prefix (prefix str)
+  "If PREFIX is prefix of STR, the string is trimmed."
+  (when (and (stringp prefix)
+             (stringp str))
+    (if (string-prefix-p prefix str)
+        (substring str (length prefix)))))
+
+(defun haskell-string-trim-suffix (suffix str)
+  "If SUFFIX is suffix of STR, the string is trimmed."
+  (when (and (stringp suffix)
+             (stringp str))
+    (if (string-suffix-p suffix str)
+        (substring str 0 (* -1 (length suffix))))))
+
 (defun haskell-string-drop-qualifier (ident)
   "Drop qualifier from given identifier IDENT.
 
@@ -170,6 +199,21 @@ If the identifier is not qualified return it unchanged."
            (match-string 1 ident))
       ident))
 
+(defun haskell-mode-message-line (str)
+  "Echo STR in mini-buffer.
+Given string is shrinken to single line, multiple lines just
+disturbs the programmer."
+  (message "%s" (haskell-mode-one-line str (frame-width))))
+
+(defun haskell-mode-one-line (str &optional width)
+  "Try to fit STR as much as possible on one line according to given WIDTH."
+  (unless width
+    (setq width (length str)))
+  (let* ((long-line (replace-regexp-in-string "\n" " " str))
+         (condensed  (replace-regexp-in-string
+                      " +" " " (haskell-string-trim long-line))))
+    (truncate-string-to-width condensed width nil nil "…")))
+
 (provide 'haskell-string)
 
 ;;; haskell-string.el ends here