The assignment of an empty list erases the content of %hash, but undef %hash erases the container. So these are different operations to choose from for the task at hand.

perl -le'print map{pack c,($-++?1:13)+ord}split//,ESEL'

In reply to Re: '%hash = ()' is slower than 'undef %hash' by shmem
in thread '%hash = ()' is slower than 'undef %hash' by rsFalse

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