Perl 在多个绑定运算符中捕获变量

Question

有没有办法在 more than binding expression 中使用捕获组并捕获所有组？

#!/usr/bin/perl

use strict;
use warnings;

countDays(1,"2015-3-21","2016-3-24");

sub countDays {
    die "Check formatting"
        unless ($_[0] =~ m/([1-7])/ &&
                $_[1] =~ m/^(\d{4})-(\d{1,2})-(\d{1,2})$/ &&
                $_[2] =~ m/^(\d{4})-(\d{1,2})-(\d{1,2})$/);

            # testing
            print "\n\n\n\n\n\n\n";

}

这仅捕获最后三个组：</code>、<code> 和 </code>。</p> <p>按照 Avinash Raj 的建议编辑预期输出：</p> <pre><code>1 2015 3 21 2016 3 24

Answer 1

不，每次成功匹配都会重置所有捕获变量。但是你可以这样做：

sub countDays {
    my @match1 = $_[0] =~ m/([1-7])/
        and
    my @match2 = $_[1] =~ m/^(\d{4})-(\d{1,2})-(\d{1,2})$/
        and
    my @match3 = $_[2] =~ m/^(\d{4})-(\d{1,2})-(\d{1,2})$/
        or die "Check formatting";

    print "@match1\n@match2\n@match3\n";
}

Answer 2

#!/usr/bin/env perl
use strict;
use warnings;

countDays(1,"2015-3-21","2016-3-24");

sub countDays {
    my $countDays = join ',', @_;

    die "Check formatting"
        unless $countDays =~
            m/([1-7]),(\d{4})-(\d{1,2})-(\d{1,2}),(\d{4})-(\d{1,2})-(\d{1,2})/;

    # testing
    print "\n\n\n\n\n\n\n";
}

Perl 在多个绑定运算符中捕获变量

Perl capture variables in multiple binding operators

regex

perl

capture-group