From: PerlFAQ Server on
This is an excerpt from the latest version perlfaq4.pod, which
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4.54: Why does defined() return true on empty arrays and hashes?

The short story is that you should probably only use defined on scalars
or functions, not on aggregates (arrays and hashes). See "defined" in
perlfunc in the 5.004 release or later of Perl for more detail.



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