我正在尝试创建一个正则表达式来捕获文本引用.
以下是文本引用的几个例句：
… and the reported results in (Nivre et al.,2007) were not representative …
… two systems used a Markov chain approach (Sagae and Tsujii 2007).
Nivre (2007) showed that …
… for attaching and labeling dependencies (Chen et al.,2007; Dredze et al.,2007).
目前,我的正则表达式是
\(\D*\d\d\d\d\)
哪个匹配示例1-3,但不匹配示例4.如何修改此示例以捕获示例4？
谢谢！
我最近为此目的使用了这样的东西：
#!/usr/bin/env perl
use 5.010;
use utf8;
use strict;
use autodie;
use warnings qw< FATAL all >;
use open qw< :std IO :utf8 >;
my $citation_rx = qr{
\( (?:
\s*
# optional author list
(?:
# has to start capitalized
\p{Uppercase_Letter}
# then have a lower case letter,or maybe an apostrophe
(?= [\p{Lowercase_Letter}\p{Quotation_Mark}] )
# before a run of letters and admissible punctuation
[\p{Alphabetic}\p{Dash_Punctuation}\p{Quotation_Mark}\s,.] +
) ? # hook if and only if you want the authors to be optional!!
# a reasonable year
\b (18|19|20) \d\d
# citation series suffix,up to a six-parter
[a-f] ? \b
# trailing semicolon to separate multiple citations
; ?
\s*
) +
\)
}x;
while (<DATA>) {
while (/$citation_rx/gp) {
say ${^MATCH};
}
}
__END__
... and the reported results in (Nivré et al.,2007) were not representative ...
... two systems used a Markov chain approach (Sagae and Tsujii 2007).
Nivre (2007) showed that ...
... for attaching and labelling dependencies (Chen et al.,2007; Dredze et al.,2007).
运行时,它会产生：
(Nivré et al.,2007) (Sagae and Tsujii 2007) (2007) (Chen et al.,2007)
