Is there a way to write a regex that fails if the line being compared has anything other than what is in the pattern? Reading that, it doesn't make much sense, so here is an example. 
while (<>) {
  if ( /\w{5}\s\w{4}/ ) { 
    print "This is a 5-letter word followed by a four-letter word\n";
  }
}

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Now that would match this:

happy dude

but it would also match this:

man, that's a happy dude

Is there some way I can make the regex match ONLY 5-letter words followed by 4-letter words, but not ANYTHING else (so that it would match "happy dude" but NOT "man, that's a happy dude")? In other words, can I force the regex to say "the entire line being compared, not just a substring, has to match this pattern"?

Some people drink from the fountain of knowledge, others just gargle.

In reply to "Complete match" regexes by DeusVult

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