You can't pass arrays (or hashes) to subs, only a sequence of zero or more scalars. There is no difference between 

f(@a)

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and 
f($a[0], $a[1], $a[2], ...)

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so you can't distinguish 

my @empty;
f(@empty)

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from 
f()

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At best, you can use prototypes to change what scalars are passed to a sub. 

sub f(;\@)

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will allow 
f(@a)     # Calls &f(\@a)

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and 
f()       # Calls &f()

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but not 
f($x, $y)

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What you want to achieve, however, can't be achieved using prototypes. You'd have to use something like Devel::CallParser.

Seeking work! You can reach me at ikegami@adaelis.com

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

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