bug#26338: 26.0.50; Collect all matches for REGEXP in current buffer

[Juri Linkov]

>> Sorry if this was said already, but why a macro and not a map-like
>> function?
> No special reason.  It's the second idea which came to my mind after
> my initial proposal was declined.  Maybe because is shorter to do:
> (with-collect-matches regexp)
> than
> (foo-collect-matches regexp nil #'identity)
>
> if you are just interested in the list of matches.  Implementing it as
> a map function might be also nice.  Don't see a big enthusiasm on
> the proposal, though :-(
>
> So far people think that it's easy to write a while loop.  I wonder if they
> think the same about the existence of `dolist': the should
> never use it and always write a `while' loop instead.  Don't think they
> do that anyway.
>
> I will repeat it once more.  I find nice, having an operator returning
> a list with matches for REGEXP.  If such operator, in addition, accepts
> a body of code or a function, then i find this operator very nice
> and elegant.

A mapcar-like function presumes a lambda where you can process every
match as you need, but going this way you'd have a temptation to
implement an analogous API from other programming languages like e.g.
https://apidock.com/ruby/String/scan