A function that takes another function as a parameter. The parameter type func[int] means "a function returning int". |
func apply(int x, func[int] f) int {
f(x);
};
any square = func(int x) int {
x * x;
};
int result = apply(5, square); # 25
|
The built-in map method on arrays is a higher-order function. It takes a callback with (index, value) parameters. |
array[int] nums = new array[int]{1, 2, 3, 4, 5};
array[int] doubled = nums.map(
func(int i, int v) int {
v * 2
}
); # [2, 4, 6, 8, 10]
|