Compare:

$\=$/;
@a = qw( d e f );
print(@a);               # prints 'def'
print(scalar(@a));       # prints '3'
print(@a==3?'3':'!3');   # prints '3'

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print accepts a list as an argument. @array returns a list of its elements in a list context.

< accepts scalars as arguments. @array returns the number of elements it has in a scalar context.

So yes, you can rely on @{$db{$key}} for your test. If you want to make it clear to yourself, use scalar(@{$db{$key}}) instead.

In reply to Re^3: Hash of arrays of arrays by ikegami
in thread Hash of arrays of arrays by Anonymous Monk

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