$ perl -MO=Deparse,-p junk
use subs ('non_commutative');
sub non_commutative {
    use warnings;
    return(17);
}
use warnings;
($x = (10 * non_commutative()));
($y = non_commutative(*10));
print("$x\n$y\n\n");
($x = (10 + non_commutative()));
($y = non_commutative(10));
print("$x\n$y\n");
junk syntax OK