Hello!

Something is going wrong in my regular expression. It works properly when I include the (?{print;}) diagnostic parts, but when I remove them that part of the regex always returns true.

It's meant to be part of a scrabble program. Given a space on the board (in this example <space><space>W) and a set of tiles (ORW), it matches words that can be played in that spot.

for( qw(row bow sow how wow crw stw wrw))

{
  print "$_\n";
  if(/
      (?(?=(.*o){1})
        (?{print "there's an o!\n";})
        (?(?!(.*r){1})
          (?{print "there's no r!\n";})
          (?=(.*w){2})
          (?{print "there's two ws!\n";})
        |
          (?{print "there's an r!\n";})
        )
      |
        (?{print "there's no o!\n";})
        (?=(.*w){2})
        (?{print "there's 2 ws!\n";})
        (?=(.*r){1})
        (?{print "there's an r!\n";})
    )
    ^..W$
  /xi)
  {
    print "YES\n\n";
  }
  else
  {
    print "NO\n\n";
  }
}

[download]

I'm pretty sure this was working some time ago when I had an earlier version of perl, but I've since updated to 5.10.0 and now it's not.

Thanks for any help

In reply to Oddity with Conditional Regex by Rabscuttle

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