For beginners: the output of a boolean operation is reliably interpreted as true or false. Everything else should be tested by comparison.

The one idiomatic exception I can think of is 

while (<INPUT>) {
...

[download]
which has an implicit boolean test in it. Nothing else springs to my mind.
Caution: Contents may have been coded under pressure.

In reply to Re: Explaining Perl truth to beginners by Roy Johnson
in thread Explaining Perl truth to beginners by shemp

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