Re: [pcre-dev] PCRE2 alpha testers wanted

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Συντάκτης: Zoltán Herczeg
Ημερομηνία:  
Προς: pcre-dev
Αντικείμενο: Re: [pcre-dev] PCRE2 alpha testers wanted
Hi Philip,

great news! This really a great step ahead. Thank you for the hard work! I will do some JIT testing in the coming weeks.

Regards,
Zoltan

ph10@??? írta:
>To PCRE2 users:
>
>Over the last few months I have been refactoring the way pcre2_compile()
>works. The new code, tests, and updated documentation have just been
>committed to the repository. You can check out PCRE2 like this:
>
>svn co svn://vcs.exim.org/pcre2/code/trunk pcre2
>
>I realized that most of the parsing could be moved into the relatively
>new pre-pass function (introduced at 10.20) that identifies named and
>numbered groups before the "real" compile. This function now creates a
>parsed version of the pattern for the actual compile, which simplifies
>things because (amongst other things) the handling of escapes and
>skipping comments happens in one place only. (More details are in the
>HACKING file.) While doing this work, I discovered a few minor bugs and
>Perl incompatibilities that I was able to fix, including:
>
>  (a) \Q\E in the middle of a quantifier such as A+\Q\E+ is now ignored
>      instead of giving an invalid quantifier error.
>  (b) {0} can now be used after a group in a lookbehind assertion;
>      previously this caused an "assertion is not fixed length" error.
>  (c) Perl always treats (?(DEFINE) as a "define" group, even if a group
>      with the name "DEFINE" exists. PCRE2 now does likewise.
>  (d) A recursion condition test such as (?(R2)...) must now refer to an
>      existing subpattern.

>
>The result of this work is that the compiled pcre2_compile.c file (the
>.o file) is almost 40% smaller on my box. Paradoxically, the source file
>is bigger, but most of that is a new debugging function that is not
>normally compiled. With that excluded, the source is just a bit bigger,
>which is probably because I put in extra comments. I have not done
>exhaustive speed tests, but some simple pcre2test timings on the
>testinput1 file suggest that the new code runs a few percent faster,
>which is pleasing.
>
>One effect of the refactoring is that some error numbers and messages
>have changed, and the pattern offset given for compiling errors is not
>always the right-most character that has been read. In particular, for a
>variable-length lookbehind assertion error it now points to the start of
>the assertion. Another change is that when a callout appears before a
>group, the "length of next pattern item" that is passed now just gives
>the length of the opening parenthesis item, not the length of the whole
>group. A length of zero is now given only for a callout at the end of
>the pattern. Automatic callouts are no longer inserted before and after
>explicit callouts in the pattern.
>
>The new code runs all the tests that I have thrown at it, but I fully
>expect that I have broken something that does not show up in the tests.
>I would be grateful if someone else could find the time to download from
>the repository and try it out in a different environment. There is no
>great rush as it is likely to be some months before the next release.
>
>Meanwhile, I will get back to a number of unrelated issues that have
>been reported over the summer.
>
>Philip
>
>--
>Philip Hazel
>
>--
>## List details at https://lists.exim.org/mailman/listinfo/pcre-dev