On Thu, 2015-10-01 at 12:26 +0200, Rainer Jung wrote:
> Since it gets more common to use the expression parser for string
> operations and not only for boolean checks, I think it would be useful
> (and powerful) to support
>
> s/PATTERN/REPLACEMENT/FLAGS
>
> and allow back references in REPLACEMENT. The operation would not try to
> do the replacement in place but create a new string according to the
> given PATTERN and REPLACEMENT.
Are you mixing two things? That's well-established regexp syntax,
but you're looking at applying it to a different class expressions.
I think the most interesting issue is to define your behaviour.
> Header set X-USER "expr=%{REMOTE_USER} =~ s/([^@]*)@.*/$1/"
Aha! In terms of the expression parser, that looks like
capturing a side-effect (as opposed to a true/false result).
Maybe it would work with something like C comma-list syntax?
But I expect the line of least resistance would be to use
plain regexp rather than expr.
--
Nick Kew
