From: Arthur Reutenauer <arthur.reutenauer@normalesup.org>
To: Mailing list for ConTeXt users <ntg-context@ntg.nl>
Subject: Re: Off-topic: Struggles with LPEG grammar
Date: Mon, 21 Dec 2020 14:38:28 +0100 [thread overview]
Message-ID: <20201221133828.ynkm2zbw7pvygkna@phare.normalesup.org> (raw)
In-Reply-To: <CALBOmsYx45L+SQLbFz3gW6MxMQa4mu-gJWbdL2iMXWbRkpA7mw@mail.gmail.com>
On Mon, Dec 21, 2020 at 02:08:11PM +0100, Mojca Miklavec wrote:
> Is this a deliberate choice, a limitation of the grammar
> expressiveness, some misuse on my side that could/should/needs to be
> implemented in a different way, or does it count as a "bug" on the
> lpeg side?
That’s definitely the way parsing expression grammars work. Or rather:
that’s the way LPeg (the only parsing expression grammar) works :-)
> For example, I wouldn't expect a regexp "b+b" to fail on "bbb" just
> because "b+" would eat all three "b"s at once (the regexp "b+b" in
> fact finds "bbb", and I would expect a less-than-totally-greedy hit
> with lpeg as well). Or is my reasoning wrong here?
Your reasoning is correct, but applies to regular expressions, not
parsing-expression grammars.
Arthur
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next prev parent reply other threads:[~2020-12-21 13:38 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-12-21 12:16 Mojca Miklavec
2020-12-21 12:46 ` Taco Hoekwater
2020-12-21 12:50 ` Taco Hoekwater
2020-12-21 13:08 ` Mojca Miklavec
2020-12-21 13:36 ` Taco Hoekwater
2020-12-21 13:47 ` luigi scarso
2020-12-21 14:10 ` Mojca Miklavec
2020-12-21 14:18 ` Taco Hoekwater
2020-12-21 14:44 ` Hans Hagen
2020-12-21 13:38 ` Arthur Reutenauer [this message]
2020-12-21 13:52 ` Hans Hagen
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