Re: Performance of `re-search-backward' vs `re-search-forward'

[Marcin Borkowski]

On 2021-04-12, at 17:13, Stefan Monnier <monnier@iro.umontreal.ca> wrote:

>> I seem to (very vaguely) remember reading that `re-search-backward' is
>> significantly slower than `re-search-forward'.  However, I can't find
>> anything about it in the docstring (nor in the Elisp reference) now.  Am
>> I even correct?
>
> I haven't looked at the code recently so my memory might be off, but
> I can't think of any reason why it should be noticeably slower, no.

So both basically move character by character and check if the regex
matches there (more or less)?

> Maybe you're confusing it with `looking-back` which is much slower than
> `looking-at`?

Yes, that was it!  Thanks!

Best,

-- 
Marcin Borkowski
http://mbork.pl