Emacs正则表达式查询替换，删除了表达式中的空间

Question

I am trying to replace an erroneous C bracing style in a file with regexes in emacs.

All

if (foo)
{
    bar();
}

and the likes must become:

if (foo) {
    bar();
}

Please let's not discuss whether it's a good idea to do that, or which bracing style is best. Please.

I am trying to achieve that with emacs' query-replace-regexp :

• match " ^Q^J +{ "
• replace with " SPC{^Q^J ", with SPC being an actual space (not showing here on SO)

Somehow, the first character in the string to replace to is not taken into account, and I end up with:

if (foo){
    bar();
}

(no space before { .)

Any idea what is happening, and how I can make sure the space gets there?

Answer 1

How about this:

(defun braces-KR-style ()
  (interactive)
  (goto-char (point-min))
  (while (search-forward-regexp "\n[[:blank:]]*?{" nil t)
    (replace-match " {" nil t))
  )