I still do not understand your original reasons for wanting to use prototypes, nor do I know if hippo's reply has dissuaded you, but if you are not dissuaded, here's an example of why prototypes are not useful as you seem to wish to use them:

c:\@Work\Perl\monks>perl -wMstrict -le
"use Data::Dump qw(dd);
 ;;
 sub S_     { my %h = @_;  dd \%h; }
 sub Sh (%) { my %h = @_;  dd \%h; }
 sub Sa (@) { my %h = @_;  dd \%h; }
 ;;
 S_(qw(a b c));
 Sh(qw(a b c));
 Sa(qw(a b c));
"
Odd number of elements in hash assignment at -e line 1.
{ a => "b", c => undef }

Odd number of elements in hash assignment at -e line 1.
{ a => "b", c => undef }

Odd number of elements in hash assignment at -e line 1.
{ a => "b", c => undef }
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