You don't say exactly HOW you check the return value against undef, but I'm guessing you're doing something like "if ($val eq 'undef')" or "if ($val == undef)", both of which are wrong.

The correct way is "if (defined $val)". This won't trigger any warnings.

In reply to Re: Warning for checking with undef by splinky
in thread Warning for checking with undef by icg

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