Path: utzoo!utgpu!water!watmath!clyde!rutgers!cmcl2!yale!Ram-Ashwin
From: Ram-Ashwin@cs.yale.edu (Ashwin Ram)
Newsgroups: comp.emacs
Subject: Re: Need mlisp for "prefix-region"
Message-ID: <22140@yale-celray.yale.UUCP>
Date: 29 Jan 88 02:05:26 GMT
References: <3910015@nucsrl.UUCP>
Sender: root@yale.UUCP
Reply-To: Ram-Ashwin@cs.yale.edu (Ashwin Ram)
Organization: Computer Science, Yale University, New Haven, CT 06520-2158
Lines: 27
In-reply-to: naim@nucsrl.UUCP (Naim Abdullah)

In article <3910015@nucsrl.UUCP>, naim@nucsrl (Naim Abdullah) writes:
>		     One thing I frequently find myself needing to
> do is prefix a region with some character. Mg has a nice function
> called "prefix-region" to do that [...]

The following function should do what you want:

(defun prefix-region (begin end prefix)
   "Prefix every line in the region between BEGIN and END with the string PREFIX."
   (interactive "r\nsPrefix: ")
   (save-excursion
      (save-restriction
         (narrow-to-region begin end)
         (goto-char (point-min))
         (while (re-search-forward "^" nil t)
            (replace-match prefix t t)))))

One problem is that if the region starts from a point in the middle of a line
(rather than at the beginning of a line), the prefix will be inserted at that
point in  the  middle of the line too.   This is pretty easy to fix if it's a
problem (I don't know what MG's prefix-region does in this situation).

-- Ashwin Ram --

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