There is a conceptual hole in Perl's arguments parsing, and choroba is spot on with his explanation.

The only flexible workaround I found using prototypes is a (;&) , which will mean you need to put your parameters in a block.

Not sure if you are willing to pay that price of surrounding your parameters in curlies, but a block can hold any number and type of list elements.

  DB<32> sub my_say (;&) { $_[0] ? say $_[0]->() : say $_ }

  DB<33> @a=('a1'..'a3'); $a="A",$b="B"; $_=666

  DB<34> my_say
666

  DB<35> my_say {@a}
a1a2a3

  DB<36> my_say {@a,$a}
a1a2a3A

  DB<37> my_say {$a,1..3}
A123

  DB<38>

[download]

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery

In reply to Re: Spotting an empty array as argument by LanX
in thread Spotting an empty array as argument by Chuma

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