I came here to suggest scalar, as in, 
perl -e 'my %x=(); print scalar %x'
0

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but then, this caused me pause: 

perl -e 'my %x=undef; print scalar %x'
1/8

[download]

In reply to Re: How to test for empty hash? by perlfan
in thread How to test for empty hash? by scareduck

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