Like most things in perl the ternary operator can both help and hinder readability.

I prefer ternary for this:

# With ternary
my $x = exists $hash{key}
      ? $hash{key}
      : 'default'

# Without
my $x;
if (exists $hash{key}) {
    $x = $hash{key};
}
else {
    $x = 'default';
}
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I'm on the fence for this:

# With ternary
my $x = $x > 5
      ? 5
      : $x + 1;

# With if

if ($x > 5) {
    $x = 5;
}
else {
   $x++;
}
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And dead set against this:

my $x = $y > 5 ? ($y = 0) : ($y = 1);
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