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From: Juanma Barranquero <lekktu@gmail.com>
To: "Andreas Röhler" <andreas.roehler@easy-emacs.de>
Cc: help-gnu-emacs@gnu.org
Subject: Re: string-match bug?
Date: Tue, 8 Dec 2009 12:35:34 +0100	[thread overview]
Message-ID: <f7ccd24b0912080335l79af9edasb781922d6a817508@mail.gmail.com> (raw)
In-Reply-To: <4B1E2DA8.3090907@easy-emacs.de>

On Tue, Dec 8, 2009 at 11:42, Andreas Röhler
<andreas.roehler@easy-emacs.de> wrote:

> Well, string-match should tell first point of occurrence if any.

This is exactly what it does.

> If we have none, as with slightly changed example
>
> (string-match "xyzzy" "foox-a-yzzybar")
> it duly returns "nil"  - and not "0" saying falsly "first point of non-occurence"

It returns nil, i.e.: there's no point in the target string at which
the regexp matches.

> (string-match "" "fooxyzzybar") asks, if there is an empty string in string.
> If yes, report the starting point of the empty string.
>
> Does string start with an empty string? IMHO not.

It returns 0, i.e.: this is the point at which the target string
matches ("" will match at the beginning of every string).

It's entirely consistent. You want string-match to answer different
questions in your first and second examples.

    Juanma




  reply	other threads:[~2009-12-08 11:35 UTC|newest]

Thread overview: 41+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <mailman.12437.1260197731.2239.help-gnu-emacs@gnu.org>
2009-12-07 15:08 ` string-match bug? Colin S. Miller
2009-12-07 15:25   ` Colin S. Miller
2009-12-07 20:37     ` Andreas Röhler
2009-12-07 21:23       ` Matthew Dempsky
2009-12-08 10:42         ` Andreas Röhler
2009-12-08 11:35           ` Juanma Barranquero [this message]
2009-12-08 11:50           ` Peter Münster
     [not found]           ` <mailman.12522.1260273034.2239.help-gnu-emacs@gnu.org>
2009-12-08 15:56             ` Stefan Monnier
     [not found]         ` <mailman.12517.1260268988.2239.help-gnu-emacs@gnu.org>
2009-12-14 13:53           ` David Kastrup
     [not found]       ` <mailman.12469.1260221021.2239.help-gnu-emacs@gnu.org>
2009-12-08  3:22         ` Barry Margolin
2009-12-08 10:50           ` Andreas Röhler
2009-12-08 11:31             ` Peter Dyballa
2009-12-08 13:55               ` Andreas Röhler
     [not found]           ` <mailman.12518.1260269458.2239.help-gnu-emacs@gnu.org>
2009-12-08 20:48             ` Barry Margolin
2009-12-08 21:23               ` Pascal J. Bourguignon
2009-12-09 16:16                 ` Stefan Monnier
2009-12-08 23:48               ` Matthew Dempsky
2009-12-09  8:05                 ` Andreas Röhler
2009-12-09 12:56                   ` Juanma Barranquero
2009-12-09 17:33                     ` Andreas Röhler
2009-12-09 18:07                       ` Matthew Dempsky
2009-12-09 18:13                         ` tomas
2009-12-09 18:59                         ` Andreas Röhler
2009-12-09 21:15                           ` Matthew Dempsky
     [not found]                         ` <mailman.12615.1260385212.2239.help-gnu-emacs@gnu.org>
2009-12-10  0:22                           ` Barry Margolin
2009-12-09 18:11                       ` tomas
2009-12-10  3:05                       ` Kevin Rodgers
     [not found]                       ` <mailman.12630.1260414617.2239.help-gnu-emacs@gnu.org>
2009-12-10  5:34                         ` Stefan Monnier
2009-12-10 10:01                           ` tomas
2009-12-10 11:00                             ` Andreas Politz
2009-12-11  4:37                               ` Kevin Rodgers
     [not found]                             ` <mailman.12651.1260442881.2239.help-gnu-emacs@gnu.org>
2009-12-14 13:59                               ` David Kastrup
     [not found]                     ` <mailman.12606.1260380004.2239.help-gnu-emacs@gnu.org>
2009-12-09 19:08                       ` Frank Fredstone
2009-12-10 19:25                         ` Andreas Röhler
2009-12-10 23:41                           ` Juanma Barranquero
     [not found]                         ` <mailman.12689.1260473128.2239.help-gnu-emacs@gnu.org>
2009-12-10 20:40                           ` Frank Fredstone
2009-12-09 21:33                       ` Stefan Monnier
2009-12-10  6:38                         ` Andreas Röhler
2009-12-14 13:51             ` David Kastrup
2009-12-07 14:55 Andreas Roehler
2009-12-07 15:31 ` Pierre Lorenzon

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