From: Bart Schaefer <schaefer@brasslantern.com>
To: Zsh Users <zsh-users@zsh.org>
Subject: Re: backreferences
Date: Thu, 15 Oct 2015 22:05:45 -0700 [thread overview]
Message-ID: <151015220545.ZM30842@torch.brasslantern.com> (raw)
In-Reply-To: <CAHYJk3Q5OL807aE9eAw+jp2ueHFO7MPswYeqU0+n0ZUnG5JqgQ@mail.gmail.com>
On Oct 16, 6:11am, Mikael Magnusson wrote:
}
} As a sidenote, (^foo)* is always useless to write, since (^foo) will
} expand to the empty string, and then the * will consume anything else.
Minor correction ... (^foo) will be the empty string only if the tested
string begins with "foo". But then * will consume the "foo", making
the (^foo) useless. Conversely if the string does not contain "foo" at
all, (^foo) will consume all of it and * will match the empty string.
However, (^foo)(*) could be very useful with backreferences, because
(^foo) puts everything up to "foo" into $match[1], and then (*) puts
from "foo" to the end into $match[2]. Which happens to be a lot like
what Ray was trying to accomplish.
} A useful way to think of (^foo) is a * that will exclude any matches
} that don't match the pattern foo.
Yes. There's a really long explanation of this in Etc/FAQ 3.27.
next prev parent reply other threads:[~2015-10-16 5:05 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-10-15 18:28 backreferences Ray Andrews
2015-10-15 23:16 ` backreferences Bart Schaefer
2015-10-16 1:16 ` backreferences Ray Andrews
2015-10-16 2:30 ` backreferences Bart Schaefer
2015-10-16 4:11 ` backreferences Mikael Magnusson
2015-10-16 4:27 ` backreferences Kurtis Rader
2015-10-16 5:42 ` backreferences Ray Andrews
2015-10-16 5:05 ` Bart Schaefer [this message]
2015-10-16 5:28 ` backreferences Bart Schaefer
2015-10-16 5:46 ` backreferences Ray Andrews
2015-10-16 11:14 ` backreferences Peter Stephenson
2015-10-16 5:36 ` backreferences Ray Andrews
2015-10-16 12:35 ` backreferences Bart Schaefer
2015-10-16 16:37 ` backreferences Ray Andrews
2015-10-17 3:33 ` backreferences Bart Schaefer
2015-10-17 5:16 ` backreferences Ray Andrews
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