Re: elisp optimization question

[Lennart Borgman (gmail)]

brad clawsie wrote:
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> Hash: SHA1
>
> hi, i use the following function to translate unicode and other
> entities found on the web into ascii that i can view in emacs-w3m. i
> am concerned that each search and replace as done in my example is
> inefficient, is there a better way to do this? i.e., is there a better
> way to group search/replace pairs? thanks in advance!
>
> (defun w3m-filter-brad (url)
>   (goto-char (point-min))
>   (while (re-search-forward "»" nil t)
>     (replace-match ">>"))
>   (goto-char (point-min))
>   (while (re-search-forward "’" nil t)
>     (replace-match "'"))
>   (goto-char (point-min))
>   (while (re-search-forward "“" nil t)
>     (replace-match "\""))
>   (goto-char (point-min))
>   (while (re-search-forward "”" nil t)
>     (replace-match "\""))
>   (goto-char (point-min))
>   (while (re-search-forward "—" nil t)
>     (replace-match "-"))
>   (goto-char (point-min))
>   (while (re-search-forward "«" nil t)
>     (replace-match "<"))
>   (goto-char (point-min))
>   (while (re-search-forward "»" nil t)
>     (replace-match ">"))
>   (goto-char (point-min))
>   (while (re-search-forward "ö" nil t)
>     (replace-match "o"))
>   )


When you write it the way you do you do not need re-search-forward, just 
search-forward since you search for strings, not regular expressions.

Another way to make it faster would perhaps be to make one regular 
expression with regexp-opt and then check the match.