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Date: Thu, 1 Oct 2015 08:33:13 -0400
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 <CALK=YjPB=xUQg2_B0p6YKocQ58GBf5YtpR1tnJnS+ua+4=G2YA@mail.gmail.com>
Subject: Re: Expression Parser: search and replace with
 s/PATTERN/REPLACEMENT/FLAGS
From: Eric Covener <covener@gmail.com>
To: Apache HTTP Server Development List <dev@httpd.apache.org>
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On Thu, Oct 1, 2015 at 6:26 AM, Rainer Jung <rainer.jung@kippdata.de> 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.
>
> I had a quick look at the flex and bison files which generate lexer and
> parser but must admit that it wasn't immediately obvious to me how to do it.
> I can try harder but first wanted to ask if there are any volunteers who
> know that technology better than me. Stefan (Frisch)? Others?
>
> Otherwise I'll try myself (and learn new stuff on the way).

I've tried and failed to hack the exact same thing in a few times.  I
agree it would be great to have.