The canonical answer is to use a hash:

my %in_set;
undef @in_set{1, 3, 7};

if( exists $in_set{ $x } ) {
    # ...
}

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The grep solution mentioned before is also common.

The other solutions posted involving modules have much more overhead than either of these two, but have strengths in various areas beyond your simple use case.

Makeshifts last the longest.

In reply to Re: writing perl function like sql IN by Aristotle
in thread writing perl function like sql IN by JAMBOID

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