flatten
Flattens the nested array given as an argument to the desired depth.
It works the same as Array.prototype.flat provided by default in JavaScript and returns the same type. However, its performance is superior.
Signature
typescript
function flatten<T, D extends number = 1>(arr: T[], depth?: D): Array<FlatArray<T[], D>>;Parameters
arr(T[]): The array to flatten.depth(D): The depth to flatten, which defaults to 1.
Returns
(Array<FlatArray<T[], D>>) A new array that has been flattened.
Examples
typescript
const array = [1, [2, 3], [4, [5, 6]]];
const result1 = flatten(array);
// Return [1, 2, 3, 4, [5, 6]]
const result2 = flatten(array, 1);
// Return [1, 2, 3, 4, [5, 6]]
const result3 = flatten(array, 2);
// Return [1, 2, 3, 4, 5, 6]