It is simply a quick and dirty if-else statement: 
return $is_true ? 'is true!' : 'is false';

# is just a one line way of saying
if ($is_true) {
  return 'is true!';
}
else {
  return 'is false!';
}

[download]

Let me elaborate a bit more (aka update):
You can even nest them: 

$a = $is_true ? 'is true!' : $was_true ? 'was true' : 'was never true'
+;

[download]
$a will contain one of the strings depending upon the value of $is_true and $was_true.

The 'hook' operator (as i like to call it) is best used for assignments, as my examples showed. Don't be tempted to do this, as it is just bad coding practice: 

$some_boolean ? do_sub1() : do_sub2();

[download]

--------------------------------------------------

perl -le '$x="jeff";$x++ for(0..4482550);print $x'

In reply to (jeffa) Re: What does the ternary statement actually do? by jeffa
in thread What does the ternary statement actually do? by Mr.T

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