diff options
Diffstat (limited to 'ChangeLog')
| -rw-r--r-- | ChangeLog | 20 |
1 files changed, 18 insertions, 2 deletions
@@ -52,7 +52,7 @@ Version 8.20 23-Sep-2011 so that no minimum is registered for a pattern that contains *ACCEPT. 8. If (*THEN) was present in the first (true) branch of a conditional group, - it was not handled as intended. + it was not handled as intended. [But see 16 below.] 9. Replaced RunTest.bat with the much improved version provided by Sheri Pierce. @@ -74,7 +74,23 @@ Version 8.20 23-Sep-2011 For "fr", it uses the Windows-specific input and output files. 14. If (*THEN) appeared in a group that was called recursively or as a - subroutine, it did not work as intended. + subroutine, it did not work as intended. [But see next item.] + +15. Consider the pattern /A (B(*THEN)C) | D/ where A, B, C, and D are complex + pattern fragments (but not containing any | characters). If A and B are + matched, but there is a failure in C so that it backtracks to (*THEN), PCRE + was behaving differently to Perl. PCRE backtracked into A, but Perl goes to + D. In other words, Perl considers parentheses that do not contain any | + characters to be part of a surrounding alternative, whereas PCRE was + treading (B(*THEN)C) the same as (B(*THEN)C|(*FAIL)) -- which Perl handles + differently. PCRE now behaves in the same way as Perl, except in the case + of subroutine/recursion calls such as (?1) which have in any case always + been different (but PCRE had them first :-). + +16. Related to 15 above: Perl does not treat the | in a conditional group as + creating alternatives. Such a group is treated in the same way as an + ordinary group without any | characters when processing (*THEN). PCRE has + been changed to match Perl's behaviour. Version 8.13 16-Aug-2011 |