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Date: Mon, 17 May 2021 16:18:23 +0200
To: Peng Yu <pengyu.ut@gmail.com>
Cc: libc-help@sourceware.org
Subject: Re: Does regex.h support lookahead?
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On Mon, May 17, 2021 at 08:42:11AM -0500, Peng Yu via Libc-help wrote:
> Hi,
>=20
> It seems that regex.h does not support lookahead. Is it so? Thanks.

You mean those "look ahead" i.e. (?=3D...) viz. (?!...) and "look behind",
i.e. (?<=3D...) viz. (?<!...) assertions of PCRE?

As far as I know, no. Regex.h supports exactly POSIX (extended) regular
expressions.

Cheers
 - t

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