undef $_

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undefines $_. To test its definedness, use
defined $_

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In case of $_, the parameter is optional.
لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ

In reply to Re: Perl DBI NULL and undef by choroba
in thread Perl DBI NULL and undef by chefchanyu

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