Get the index of the element in the given array

indexOf.js

/**
 * Get the index of the element in the given array
 *
 * @param {any} element the element to find
 * @param {any[]} array the array to be searched
 * @param {number} [fromIndex=0] the array index at which to begin the search
 * @returns {number} returns the index of the element. if the element is not found, -1 is returned.
 */
var indexOf = function (element, array, fromIndex) {
    if (typeof Array.prototype.indexOf === 'function') {
        indexOf = function (element, array, fromIndex) {
            fromIndex = typeof fromIndex === 'number' ? fromIndex : 0;
            return array.indexOf(element, fromIndex);
        };
    } else {
        indexOf = function (element, array, fromIndex) {
            var i = typeof fromIndex === 'number' ? fromIndex : 0;
            var l = array.length;

            while (i < l) {
                if (element === array[i]) {
                    return i;
                }
                i += 1;
            }

            return -1;
        };
    }

    return indexOf(element, array, fromIndex);
};