> Hadn't heard about !!0 and !!1 either.

I hope it's clear that ! is just the logical negation operator.

Double negations are a very common idiom, you will find it in many languages, also in JS.

!!$a is in the same idiomatic niche like 0+$a or "".$a of explicit casting to a certain type without altering the value. Just Boolean now instead of number or string.

Cheers Rolf
(addicted to the Perl Programming Language :)
see Wikisyntax for the Monastery

In reply to Re^3: Why is Dumper returning "!!1" for true file test? by LanX
in thread Why is Dumper returning "!!1" for true file test? by nysus

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