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

[Juri Linkov]

> we have `count-matches' in replace.el, which returns the
> number of matches of a regexp.  Why not to have an standard
> function `collect-matches' as well?
>
> I know `xref-collect-matches' but it uses grep program: some users might
> not have grep installed, or they may prefer to use Emacs regexps.
>
> I've being using for a while something similar than the patch below.
> Probably it doesn't need to be a command, just a normal function.
>
> What do you think?

But there is already the occur-collect feature implemented in occur-1
and occur-read-primary-args.  Why would we need a separate command?