Re: substitution groups and patterns i replace string (Emacs' \\1 etc.)

[Emanuel Berg <embe8573@xxxxxxxxxxxxx>]

Peter Stephenson <p.stephenson@xxxxxxxxxxx> writes:

>> When I do substitution, can I do groups and
>> patterns like in Emacs with \\1, \\2 to reference
>> the particular matches, and thus construct the
>> replace string out of them any way I like?
>
> You do it with $match, and if you need to refer to
> positions in the original string, $mbegin and $mend.
> See the description of the (#b) pattern in the
> zshexpn manual page.

I have now checked out the zshexpn(1) man page but the
examples there are very complicated!

> local -a match mbegin mend
>
> if [[ $url = (#b)http://(*) ]]; then print $match[1]
> fi

Thanks, but this syntax is very bulky compared to
Emacs and sed. How it is supposed to be used for
a stream of text or a variable with several hit
instances? I'm not saying it can't be done only
compared to Emacs (and sed) it seems
unnecessarily complicated.

Perhaps Emacs/sed syntax in this case is something
that can be added to zsh?

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