Well, a comparison like $x < $y returns '' for false and 1 for true. However, the comparison $x <=> $y returns -1 if $x is less than $y, 0 if $x is equal to $y, and 1 if $x is greater than $y. This means that you could do: 
my %messages = (
  -1 => "too low",
   0 => "just right",
   1 => "too high",
);

while (...) {
  print $messages{ $guess <=> $answer }, "\n";
}

[download]
You could also do this as an array: 
my @messages = (
  "just right",
  "too high",
  "too low",
);

print $messages[$guess <=> $answer];

[download]
although I'd guess several monks here might take offense to that approach.
Jeff japhy Pinyan, P.L., P.M., P.O.D, X.S.: Perl, regex, and perl hacker
How can we ever be the sold short or the cheated, we who for every service have long ago been overpaid? ~~ Meister Eckhart

In reply to Re: Having an expression as a hash key by japhy
in thread Having an expression as a hash key by sub_chick

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