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 }