/[pcre]/code/trunk/doc/pcrecompat.3
ViewVC logotype

Diff of /code/trunk/doc/pcrecompat.3

Parent Directory Parent Directory | Revision Log Revision Log | View Patch Patch

revision 636 by ph10, Sat Jul 23 16:19:50 2011 UTC revision 637 by ph10, Sun Jul 24 17:44:12 2011 UTC
# Line 20  in the main Line 20  in the main
20  .\"  .\"
21  page.  page.
22  .P  .P
23  2. PCRE does not allow repeat quantifiers on assertions. Perl permits them, but  2. PCRE allows repeat quantifiers only on parenthesized assertions, but they do
24  they do not mean what you might think. For example, (?!a){3} does not assert  not mean what you might think. For example, (?!a){3} does not assert that the
25  that the next three characters are not "a". It just asserts that the next  next three characters are not "a". It just asserts that the next character is
26  character is not "a" three times.  not "a" three times (in principle: PCRE optimizes this to run the assertion
27    just once). Perl allows repeat quantifiers on other assertions such as \b, but
28    these do not seem to have any use.
29  .P  .P
30  3. Capturing subpatterns that occur inside negative lookahead assertions are  3. Capturing subpatterns that occur inside negative lookahead assertions are
31  counted, but their entries in the offsets vector are never set. Perl sets its  counted, but their entries in the offsets vector are never set. Perl sets its
# Line 171  Cambridge CB2 3QH, England. Line 173  Cambridge CB2 3QH, England.
173  .rs  .rs
174  .sp  .sp
175  .nf  .nf
176  Last updated: 23 July 2011  Last updated: 24 July 2011
177  Copyright (c) 1997-2011 University of Cambridge.  Copyright (c) 1997-2011 University of Cambridge.
178  .fi  .fi

Legend:
Removed from v.636  
changed lines
  Added in v.637

  ViewVC Help
Powered by ViewVC 1.1.5