add_ten: i32 -> i32: @ value: i32 { value + 10 }
double: i32 -> i32: @ value: i32 { value * 2 }

# Stages bind tighter than prefix and infix operators: -{3->add_ten} + 2 * {3->double}.
mixed: i32: -3->add_ten + 2 * 3->double - {1 + 1}->double