title: nthElement tags: array,beginner

Returns the nth element of an array.[Curry Function]

Use Array.prototype.slice() to get an array containing the nth element at the first place. If the index is out of bounds, return undefined. Omit the second argument, n, to get the first element of the array.

const nthElement = curry(
  (n = 0, arr: any[]) => (n === -1 ? arr.slice(n) : arr.slice(n, n + 1))[0],
  2
);

nthElement(["a", "b", "c"], 1); // 'b'
nthElement(["a", "b", "b"], -3); // 'a'

nthElement(-1, [1, 2, 3, 4, 5]), 5;

// curry power
const third = nthElement(2);
const last = nthElement(-1);
third([1, 2, 3]); // 3
last([1, 2, 3, 4, 5]); // 5