var my_list = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
print(my_list[3]); # expect: 4

class MyClass {

    __init__() {
        this.x = 1;
        this.y = 2;
    }

    __getitem__(a) {
        if (a == 0) {
            return this.x;
        }
        if (a == 1) {
            return this.y;
        }
        return nil;
    }
}

var my_object = MyClass();
print(my_object[0]); # expect: 1
print(my_object[1]); # expect: 2
print(my_object[2]); # expect: nil

class BadClass {}

var bad_object = BadClass();
bad_object[1]; # expect runtime error: Undefined property '__getitem__'.