Perl，在由未知字符分隔的同一行中多次匹配一个模式 [英] Perl, match one pattern multiple times in the same line delimited by unknown characters

问题描述

我已经能够找到与此类似但不完全相同的问题.如何在由未知字符分隔的同一行中多次匹配一个正则表达式模式?

I've been able to find similar, but not identical questions to this one. How do I match one regex pattern multiple times in the same line delimited by unknown characters?

例如，假设我想匹配模式 HEY.我想识别以下所有内容:

For example, say I want to match the pattern HEY. I'd want to recognize all of the following:

嘿

嘿嘿

嘿xjfkdsjfkajHEY

HEYxjfkdsjfkajHEY

所以我在那里数了 5 个 HEY.所以这是我的程序，它适用于除最后一个之外的所有内容:

So I'd count 5 HEYs there. So here's my program, which works for everything but the last one:

open ( FH, $ARGV[0]);
while(<FH>)
{
  foreach $w ( split )
  {
      if ($w =~ m/HEY/g)
      {
            $count++;
      }
  }
}

所以我的问题是如何替换那个 foreach 循环，以便我可以识别由未知配置中的奇怪字符分隔的模式(如上例所示)?

So my question is how do I replace that foreach loop so that I can recognize patterns delimited by weird characters in unknown configurations (like shown in the example above)?

感谢迄今为止的精彩回复.我刚刚意识到我还需要另一件事，我在下面发表了评论.

Thanks for the great responses thus far. I just realized I need one other thing though, which I put in a comment below.

一个问题:有没有办法保存匹配的术语?所以就像在我的情况下，有什么方法可以引用 $w(假设正则表达式更复杂，我想将它存储在出现次数的哈希中)

One question though: is there any way to save the matched term as well? So like in my case, is there any way to reference $w (say if the regex was more complicated, and I wanted to store it in a hash with the number of occurrences)

因此，如果我正在匹配一个真正的正则表达式(比如一个字母数字字符序列)并希望将其保存在哈希中.

So if I was matching a real regex (say a sequence of alphanumeric characters) and wanted to save that in a hash.

推荐答案

一种方法是捕获字符串的所有匹配项并查看您得到了多少.像这样:

One way is to capture all matches of the string and see how many you got. Like so:

open (FH, $ARGV[0]);
while(my $w = <FH>) {
    my @matches = $w =~ m/(HEY)/g;
    my $count = scalar(@matches);
    print "$count\t$w\n";
}

是的，有！只需遍历所有匹配项，并使用捕获变量来增加哈希中的计数:

Yes, there is! Just loop over all the matches, and use the capture variables to increment the count in a hash:

my %hash;
open (FH, $ARGV[0]);
while (my $w = <FH>) {
   foreach ($w =~ /(HEY)/g) {
       $hash{$1}++;
   }
}

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