Hi,
kindly acknowledge if the following is a defect in PCRE library or not.
Here, I'm giving a regular expression which consists of an empty character class
to the pcretest program which accepts it without giving any error.
mladhe@linux61:~/softwares/pcre-7.8/cmake] ./pcretest
PCRE version 7.8 2008-09-05
re> /[^\x00-\xff]/
data> \x00
No match
data> \xff
No match
data> \x80
No match
data>
It does not match any character as shown by a few examples above.
Thanks,
Mahendra Ladhe
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Date: Tue, 4 Nov 2008 20:34:29 +0000 (GMT)
From: Philip Hazel <ph10@???>
To: Mahendra Ladhe <lml108@???>
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Subject: Re: [pcre-dev] pcretest program accepts empty character class
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On Tue, 4 Nov 2008, Mahendra Ladhe wrote:
> ?? kindly acknowledge if the following is a defect in PCRE library or
> not. Here, I'm giving a regular expression which consists of an empty
> character class to the pcretest program which accepts it without
> giving any error.
>
> mladhe@linux61:~/softwares/pcre-7.8/cmake] ./pcretest
> PCRE version 7.8 2008-09-05
>
> ? re> /[^\x00-\xff]/
> data> \x00
> No match
> data> \xff
> No match
> data> \x80
> No match
> data>
>
> It does not match any character as shown by a few examples above.
It is exactly compatible with Perl, which gives the same result. Of
course, Perl is permanently in Unicode mode these days, whereas PCRE can
be in either, but I think that the above is still the correct behaviour.
It is not the only construct that always fails (it wouldn't always fail
in UTF-8 mode, of course). Constructs like (?!) also always fail.
Philip
--
Philip Hazel
--1750319812-1944530493-1225830869?6649--
