if class_room.is_empty then class_room.close_windows class_room.switch_lights_off class_room.lock_door .
if then instruction
if then else instruction
variable message string if the_sun_shines then message = "Antonio is very happy." else message = "Antonio is happy." .
Note that, as we’ve seen previously in chapter Expressions and operators, we can also use an
if expression (instead of an
const message = if the_sun_shines then "Antonio is very happy." else "Antonio is happy."
This is the preferred code, because the code is shorter and we use a constant instead of a variable.
if then else if instruction
const num_orders = ... variable message string if num_orders =v 0 then message = "There are no orders." else if num_orders =v 1 then message = "There is one order." else if num_orders <= 5 then message = "There are 5 orders or less." else message = "There are more than 5 orders" .