use feature 'say';
sub p_foo () {
    my $n = 12 * ( $_[0] // 1 );
    return $n;
}

sub foo {
    my $n = 12 * ( $_[0] // 1 );
    return $n;
}
say "p_foo: ", p_foo + 3;
say "foo: ", foo + 3;