是否可以在一串单引号词中提取第n个匹配？
use strict;
use warnings;
my $string1 = "'I want to' 'extract the word' 'Perl','from this string'";
my $string2 = "'What about','getting','Perl','from','here','?'";
sub extract_quoted {
my ($string,$index) = @_;
my ($wanted) = $string =~ /some_regex_using _$index/;
return $wanted;
}
extract_wanted ($string1,3); # Should return 'Perl',with quotes
extract_wanted ($string2,with quotes
解决方法
你可以试试：
sub extract_quoted {
my ($string,$index) = @_;
while($string =~ /'(.*?)'/g) {
$index--;
return $1 if(! $index); # return $1 if index became 0.
}
return; # not found - returns undef or () depending on context.
}