This is an example in 'perl cookbook': 
 sub dequote;
$poem = dequote <<EVER_ON_AND_ON;
    Now far ahead the Road has gone,
      And I must follow, if I can,
    Pursuing it with eager feet,
      Until it joins some larger way
    Where many paths and errands meet.
      And whither then? I cannot say.
              --Bilbo 
EVER_ON_AND_ON
print "Here's your poem: \n\n$poem\n";
sub dequote {
    local $_ = shift;
    
    my ($white,$leader);
    if (/^\s*(?:([^\w\s]+)(\s*).*\n)(?:\s*\1\2?.*\n)+$/){
        ($white,$leader) = ($2,quotemeta($1)); 
    }else {
        ($white,$leader) = (/^(\s+)/,'');
    }
    
    s/^\s*?$leader(?:$white)?//gm;
    return $_;
}

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I have a question about what match the [^\w\s\]+ in the string.

In reply to a match question by jinqiyi

Title:
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and:  <code> code here </code>
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