Perl正则表达式:如何知道匹配数 [英] Perl regex: how to know number of matches

问题描述

我正在遍历一系列正则表达式，并将其与文件中的行进行匹配，如下所示:

I'm looping through a series of regexes and matching it against lines in a file, like this:

for my $regex (@{$regexs_ref}) {
    LINE: for (@rawfile) {
        /@$regex/ && do {
            # do something here
            next LINE;
        };
    }
}

有没有办法让我知道我已经进行了多少次匹配(以便我可以相应地进行处理……)?

Is there a way for me to know how many matches I've got (so I can process it accordingly..)?

如果不是这样，那是错误的方法..?当然，除了遍历每个正则表达式外，我还可以为每个正则表达式编写一个配方.但是我不知道什么是最佳做法?

If not maybe this is the wrong approach..? Of course, instead of looping through every regex, I could just write one recipe for each regex. But I don't know what's the best practice?

推荐答案

如果您在列表上下文中进行匹配(即，基本上是分配给列表)，则会在列表中获得所有匹配项和分组.然后，您可以仅在标量上下文中使用该列表来获取匹配数.

If you do your matching in list context (i.e., basically assigning to a list), you get all of your matches and groupings in a list. Then you can just use that list in scalar context to get the number of matches.

还是我误解了这个问题?

Or am I misunderstanding the question?

示例:

my @list = /$my_regex/g;
if (@list)
{
  # do stuff
  print "Number of matches: " . scalar @list . "\n";
}

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