Re: Our regex vs. POSIX on "longest match"

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От Tom Lane
Тема Re: Our regex vs. POSIX on "longest match"
Дата
Msg-id 2033.1330892403@sss.pgh.pa.us
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Ответ на Re: Our regex vs. POSIX on "longest match"  (hubert depesz lubaczewski <depesz@depesz.com>)
Ответы Re: Our regex vs. POSIX on "longest match"
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hubert depesz lubaczewski <depesz@depesz.com> writes:
> I stand on position that mixing greedy and non-greedy operators should
> be possible, and that it should work according to POLA - i.e. greedines
> of given atom shouldn't be influenced by other atoms.

[ shrug... ]  That sounds good, but it's pretty much vacuous as far as
defining a principled alternative behavior goes.  It's easy to
demonstrate cases where atoms *must* be influenced by other ones.
A trivial example is(.*)(.*)
It doesn't matter whether the second atom is greedy or not: it's not
going to get to eat anything because the first one does instead.
IOW this is just the same as(.*)(.*?)
--- they are both overall-greedy.
        regards, tom lane


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