Hi Monkees

I got a very useful regex in answer to a question yesterday, but I'm confused as to why it's not a greedy regex.

Consider the following (similiar) regexs - the first one is the one that's puzzling me. The second is greedy as I'd expect; the third is non-greedy as I'd expect, but I don't understand why the first one is non-greedy as well.

$_ = 'fooxbarbar';

# Not greedy - why not?
if(/(foo)(((?!bar).){1,5})bar/){
  print "1 Matched:$1 $2\n";
}
else{
  print "1 Not Matched\n";
}

# Greedy - as we'd expect
if(/(foo)(?!bar)((.){1,5})bar/){
  print "2 Matched:$1 $2\n";
}
else{
  print "2 Not Matched\n";
}

# Not Greedy - as we'd expect
if(/(foo)(?!bar)((.){1,5}?)bar/){
  print "3 Matched:$1 $2\n";
}
else{
  print "3 Not Matched\n";
}

[download]

Any explanation most appreciated...

Tom Melly, tom@tomandlu.co.uk

In reply to Why isn't this regex greedy? by Melly

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