findIndex

Finds the index of first element in an array that satisfies a predicate function.

Throws

  • Error: If the array is empty.
  • Error: If no element in the array satisfies the predicate function.

Type

type findIndex = <E>(predicate: ((e: E) => boolean)) => (a: Array<E>) => number

Example

import {findIndex} from 'fnxt/array';

function isEven(num: number): boolean {
  return num % 2 === 0;
}

const array = [1, 2, 3, 4, 5];
const findEven = findIndex(isEven);
findEven(array) // -> 1

See Also