Congratulations. You have stumbled on the least useful feature of Perl hashes. :)

Per perldata:

If you evaluate a hash in scalar context, it returns false if the hash is empty. If there are any key/value pairs, it returns true; more precisely, the value returned is a string consisting of the number of used buckets and the number of allocated buckets, separated by a slash. This is pretty much useful only to find out whether Perl's internal hashing algorithm is performing poorly on your data set.

In reply to Re: Effect of scalar function on hash by friedo
in thread Effect of scalar function on hash by bowei_99

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