Those aren't arguments, they're prototypes

perldoc -f sub 

sub NAME BLOCK
sub NAME (PROTO) BLOCK
sub NAME : ATTRS BLOCK
sub NAME (PROTO) : ATTRS BLOCK
        This is subroutine definition, not a real function *per se*.
        Without a BLOCK it's just a forward declaration. Without a NAME,
        it's an anonymous function declaration, and does actually return
        a value: the CODE ref of the closure you just created.

        See perlsub and perlref for details about subroutines and
        references, and attributes and Attribute::Handlers for more
        information about attributes.

In reply to Re: Quick question on a Perl Code! by Anonymous Monk
in thread Quick question on a Perl Code! by dudydude

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