Case conversion of file name (regexp) in Emacs file browser

Question

I have a similar problem to that addressed in

Emacs: regular expression replacing to change case

I want to use Emacs' file browser mode Dired to rename a file from 08 - hey you.mp3 to 08 - Hey you.mp3.

I type % R to replace ^\([0-9]* - \)\([a-z]\)\(.*\)$ by \1\,(upcase \2)\3 and I get an error

Invalid use of `\' in replacement text

When I query-replace-regexp a similar regexp \([0-9]* - \)\([a-z]\)\(.*\) by \1\,(upcase 2)\3 in a normal text buffer I don't have problems. The only input difference are the enclosing ^ and $, that are required as explained in http://www.gnu.org/software/emacs/manual/html_node/emacs/Transforming-File-Names.html#Transforming-File-Names, however the source of error seems to be the \,(upcase ), which seems not usable in Dired, since I don't have this error when I use for example \1\3\2as replace regexp.

I am using Emacs 23.2.1

Answer 1

% R in dired calls dired-do-rename-regexp which ends up calling replace-match from dired-string-replace-match, and replace-match does not support elisp replacements.

What you can do is take advantage of wdired which allows you to edit the directory listing as plain text.

C-xC-q (i.e. the usual toggle-read-only binding) will toggle between dired and wdired. Once in wdired, you can use a normal search and replace, including the elisp replacement pattern.