Re: A variant of match-end, but after replacement?

[Pascal J. Bourguignon]

Barry Margolin <barmar@alum.mit.edu> writes:

> In article <mailman.7160.1437335923.904.help-gnu-emacs@gnu.org>,
>  Marcin Borkowski <mbork@mbork.pl> wrote:
>
>> On 2015-07-19, at 15:41, Pascal J. Bourguignon <pjb@informatimago.com> wrote:
>> 
>> > Marcin Borkowski <mbork@mbork.pl> writes:
>> >
>> >>>     (let ((old-end (prog1 (match-end 1)
>> >>>                      (replace-match "newtext" t t string 1)))) 
>> >>>        (do-something old-end))
>> >>
>> >> Still not there - I can't assume that "newtext" will have the same
>> >> length as the thing it replaced...
>> >
>> > Sorry, I misread what you wanted. 
>> >
>> >     (let ((new-end (+ (prog1 (match-beginning 1)
>> >                          (replace-match new-text t t string 1)))
>> >                       (length new-text)))
>> >        (do-somthing-from new-end))
>> 
>> Thanks!  That's easy, and indeed it will work, since the length of the
>> replacement is fixed in my use-case.
>
> Yeah, this would be trickier if new-text contained back-references.

Not very much:

    (let ((end        (match-end 1))
          (new-string (replace-match new-text t t string 1)))
      (do-something-from new-string
                         (+ end (- (length string) (legnth new-string)))))


-- 
__Pascal Bourguignon__                 http://www.informatimago.com/
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