Re: Trimming strings, /emacs/lisp/emacs-lisp/subr-x.el modification

[Andreas Schwab]

On Mai 10 2017, Eli Zaretskii <address@hidden> wrote:

>> From: Andreas Schwab <address@hidden>
>> Cc: Eli Zaretskii <address@hidden>,  Michael Heerdegen
>>  <address@hidden>,  Mark Oteiza <address@hidden>,
>>   address@hidden,  Johan Bockgård <address@hidden>,
>>   address@hidden
>> Date: Tue, 09 May 2017 18:37:47 +0200
>> 
>> > Ok, so we agree that we don't add \\( \\) to the regexp and that we expect 
>> > the caller to send a correct regexp as is the case for split-string, is 
>> > that correct ?
>> 
>> If you want to modify a regexp you need to make sure to preserve its
>> semantics.
>
> Can you give an example of a regexp whose semantics might change by
> adding \\(..\\)?

If you have any backrefs, their numbers change.

Andreas.

-- 
Andreas Schwab, SUSE Labs, address@hidden
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