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.\" |
.\" |
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page. |
page. |
22 |
.P |
.P |
23 |
2. PCRE does not allow repeat quantifiers on lookahead assertions. Perl permits |
2. PCRE does not allow repeat quantifiers on assertions. Perl permits them, but |
24 |
them, but they do not mean what you might think. For example, (?!a){3} does |
they do not mean what you might think. For example, (?!a){3} does not assert |
25 |
not assert that the next three characters are not "a". It just asserts that the |
that the next three characters are not "a". It just asserts that the next |
26 |
next character is not "a" three times. |
character is not "a" three times. |
27 |
.P |
.P |
28 |
3. Capturing subpatterns that occur inside negative lookahead assertions are |
3. Capturing subpatterns that occur inside negative lookahead assertions are |
29 |
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 |
163 |
.rs |
.rs |
164 |
.sp |
.sp |
165 |
.nf |
.nf |
166 |
Last updated: 31 October 2010 |
Last updated: 02 May 2011 |
167 |
Copyright (c) 1997-2010 University of Cambridge. |
Copyright (c) 1997-2011 University of Cambridge. |
168 |
.fi |
.fi |