sub show_args {
   print(join(', ', @_), "\n");
}

my %hash = ( a=>1, b=>2, c=>3 );
show_args(%hash);  # c, 3, a, 1, b, 2

##</code><code>##

my %hash = ( a=>1, b=>2, c=>3 );
show_args(%hash, "d", 4);  # c, 3, a, 1, b, 2, d, 4