I am searching for multi-line entities in a string, and while I now have working code, I see a quirk in the use of qr// that I did not expect. Here is the example - I have changed the code to look for HTML comments, which illustrates the quirk. 

  #! /usr/bin/perl -w
  use strict;

  my $html = qq{
  blah
  <!-- comment -->
  blah
  <!--
   comment
  -->
  blah
  };

  print "m: $_\n" for $html =~ /(<!--.*?-->)/sg;

  my $r = qr/<!--.*?-->/;
  print "qr: $_\n" for $html =~ /($r)/sg;

  $r = qr/<!--.*?-->/s;
  print "qrs: $_\n" for $html =~ /($r)/g;

[download]
The output is: 
  m: <!-- comment -->
  m: <!--
   comment
  -->
  qr: <!-- comment -->
  qrs: <!-- comment -->
  qrs: <!--
   comment
  -->

[download]
The quirk is that the s modifier to the regex must be applied to the qr// construct, and may not be applied to the matching later. The g modifier, and the capturing parens may be added, but not the s.

Do I have this right? Is there sense, order and logic behind not being able to override these qr// modifiers later?

In reply to Unexpected qr// behavior by pbeckingham

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