replace-regexp

Arguments: string regexp to-string &rest args &key count start end &allow-other-keys

Replace occurrences of regexp in string with to-string. Regular expression groups in regexp can be referenced with \n in to-string. If count is nil or t, replace all occurrences; if a number, replace that number of occurrences. This function accepts all the following match-regexp keywords: newlines-special, case-fold, shortest, start and end, and passes them to match-regexp (used for finding the matches in string). Note that using start and end might be rather inefficient if used repeatedly on a large string, since for each call to replace-regexp, a new string will be created.

Examples:

(replace-regexp "xxx yyy zzz xxx yyy zzz" "xxx" "yyy")
  RETURNS "yyy yyy zzz yyy yyy zzz"
(replace-regexp "xxx yyy zzz xxx yyy zzz" "xxx" "RR")
  RETURNS "RR yyy zzz RR yyy zzz"
(replace-regexp "123 yyy zzz 123 yyy zzz 123" "y" "WHY")
  RETURNS "123 WHYWHYWHY zzz 123 WHYWHYWHY zzz 123"

(replace-regexp "xxx yyy zzz xxx yyy zzz xxx" "xxx" "yyy"
		:start 3 :end 20)
  RETURNS "xxx yyy zzz yyy yyy zzz xxx"
(replace-regexp "xxx yyy zzz xxx yyy zzz xxx" "xxx" "RR"
                :start 3 :end 20)
  RETURNS "xxx yyy zzz RR yyy zzz xxx"

(replace-regexp "xxx yyy zzz xxx yyy zzz xxx" "xxx" "yyy"
               :start 3 :end 23)
  RETURNS "xxx yyy zzz yyy yyy zzz xxx"

(replace-regexp "123 yyy zzz 123 yyy zzz 123" "123" "yyy"
                :start 3 :end 27)
  RETURNS "123 yyy zzz yyy yyy zzz yyy"
(replace-regexp "123 yyy zzz 123 yyy zzz 123" "123" "9999"
                :start 3 :end 27)
"123 yyy zzz 9999 yyy zzz 9999"

;; Here is a more complicated example that extracts some 
;; fields out a standard Unix passwd entry:

(replace-regexp "joe:*:512:50:Joe User:/home/joe:/bin/csh"
		"^\\([^:]*\\):[^:]*:\\([0-9]*\\):[0-9]*:\\([^:]*\\):.*$"
		"Login {\\1} Full Name {\\3} UID {\\2}")
"Login {joe} Full Name {Joe User} UID {512}"

;; Here is is in action:

Here it is in action:

(with-open-file (f "/etc/passwd")
  (loop repeat 5
      as entry = (read-line f nil nil)
      while entry
      collect (replace-regexp
	       entry
	       "^\\([^:]*\\):[^:]*:\\([0-9]*\\):[0-9]*:\\([^:]*\\):.*$"
	       "Login {\\1} Full Name {\\3} UID {\\2}")))
("Login {root} Full Name {system PRIVILEGED account} UID {0}"
 "Login {+} Full Name {} UID {0}"
 "Login {daemon} Full Name {system background account} UID {1}"
 "Login {bin} Full Name {system librarian account} UID {3}"
 "Login {uucp} Full Name {UNIX-to-UNIX Copy} UID {4}")

Copyright (c) 1998-2001, Franz Inc. Berkeley, CA., USA. All rights reserved.
Documentation for Allegro CL version 6.1 update # 1. This page was not revised.
Created 2001.12.15.