Subject: Re: bug#13687: /srv/bzr/emacs/trunk r111878: * lisp/replace.el (read-regexp): Let-bind `default' to the first

From: Jambunathan K <[email-masked]>
Date: Fri, 08 Mar 2013 18:32:36 +0530

Juri Linkov <[email-masked]> writes:

> 2. Add a new defcustom like:
>    (defcustom minibuffer-defaults '((highlight-regexp-default . tag-at-point)
>                                     (rgrep . history)
>                                     (occur . tag-at-point)
>                                     (how-many . history)
>                                     ...))
>    Cons: Too large list of commands for one option.

I am attaching a patch that handles `occur'.  I will commit this patch
tomorrow.

ps: I have never used how-many. The defaults for grep and rgrep never
bothered me.  So I leave these two commands out of my current scope.

=== modified file 'lisp/ChangeLog'
--- lisp/ChangeLog	2013-03-08 08:11:28 +0000
+++ lisp/ChangeLog	2013-03-08 12:52:16 +0000
@@ -1,5 +1,11 @@
 2013-03-08  Jambunathan K  <[email-masked]>
 
+	* replace.el (occur-read-regexp-defaults-function): New var.
+	(occur-read-regexp-defaults): New defun.
+	(occur-read-primary-args): Propagate above change (bug#13892).
+
+2013-03-08  Jambunathan K  <[email-masked]>
+
 	* hi-lock.el (hi-lock-read-regexp-defaults-function): New var.
 	(hi-lock-read-regexp-defaults):	 New defun.
 	(hi-lock-line-face-buffer, hi-lock-face-buffer)

=== modified file 'lisp/replace.el'
--- lisp/replace.el	2013-03-08 04:18:16 +0000
+++ lisp/replace.el	2013-03-08 12:45:40 +0000
@@ -1135,12 +1135,33 @@ which means to discard all text properti
   :group 'matching
   :version "22.1")
 
+(defvar occur-read-regexp-defaults-function
+  'occur-read-regexp-defaults
+  "Function that provides default regexp(s) for occur commands.
+This function should take no arguments and return one of nil, a
+regexp or a list of regexps for use with occur commands -
+`occur', `multi-occur' and `multi-occur-in-matching-buffers'.
+The return value of this function is used as DEFAULTS param of
+`read-regexp' while executing the occur command.  This function
+is called only during interactive use.
+
+For example, to check for occurrence of a symbol at point by
+default use
+
+    \(setq occur-read-regexp-defaults-function
+	  'find-tag-default-as-regexp\).")
+
+(defun occur-read-regexp-defaults ()
+  "Return the latest regexp from `regexp-history'.
+See `occur-read-regexp-defaults-function' for details."
+  (car regexp-history))
+
 (defun occur-read-primary-args ()
   (let* ((perform-collect (consp current-prefix-arg))
          (regexp (read-regexp (if perform-collect
                                   "Collect strings matching regexp"
                                 "List lines matching regexp")
-                              (car regexp-history))))
+                              (funcall occur-read-regexp-defaults-function))))
     (list regexp
 	  (if perform-collect
 	      ;; Perform collect operation