my first thought here was Regexp::Common::Comment ... Looking in its source, it basically does s#//[^\n]*$##s; It's interesting to note that it behaves in the same way as the regexp GrandFather demo'd above, especially with *str = "//\"//";

tye's example (though i had to make it s#foo#bar#xgm instead of s<foo><bar>xgm before it would compile) does work with GrandFather's test cases.

use warnings;

use Regexp::Common qw /comment/;

while(<DATA>){
  my ($line, $simple, $RE, $tye) = ($_)x4;
  $simple =~ s#//[^\n]*$##s;
  $RE =~ s#$RE{comment}{Portia}#\n#;
  $tye =~ s#
  (^
    (?:
        [^/'"]+
      | '([^'\\]+|\\.)*'
      | "([^"\\]+|\\.)*"
      | (?<!/)/(?!/)
    )*
  )
  //.*
  #$1#xgm;
  print "  [DATA] $line";
  print "[simple] $simple";
  print "    [RE] $RE";
  print "   [tye] $tye";
  print "\n";
}
__DATA__
blah // comment
/* //
*/
/*
*/
*str = "//\"//";
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