in reply to passing anonymous empty array reference to subroutine

Use square brackets: 
foo([]);

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لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ

In Section Seekers of Perl Wisdom