# Structs and Methods

# The keyword `struct` is used to define structures
# that hold multiple members:
struct Point(x:Int, y:Int)

    # Methods are any function defined inside of the
    # indented area below a struct definition.

    # There is no implicit `self` argument, only the
    # arguments you explicitly define.
    func abs(p:Point -> Point)
        return Point(p.x.abs(), p.y.abs())
    
    # Constants can be declared inside of a struct's namespace:
    ZERO := Point(0, 0)

    # Arbitrary functions can also be defined here:
    func squared_int(x:Int -> Int)
        return x * x

func main()

    # You can create a struct instance like this:
    p := Point(x=3, y=-4)

    assert p == Point(x=???, y=???)

    assert Point.ZERO == Point(x=???, y=???)

    assert p.x == ???
    assert p.y == ???

    assert p.abs() == ???

    assert Point.squared_int(5) == ???