G'day catfish1116,

The advice from ++haukex is sound.

As of Perl v5.12.0, length will return a FALSE value for "an undefined value or a 'blank' value" (see "perl5120delta: Other potentially incompatible changes"). If you have that version (or later) you won't need to also use defined.

See also:

• perlintro and, in particular, its "Safety net" section.
• The use function: note what it says about v5.12.0.