Rewriting map function

myMap.js

Array.prototype.myMap = function (callback, thisArg) {
	if (!thisArg) thisArg = this
	if (!Array.isArray(thisArg)) throw new Error('Not an Array')
	if (typeof callback !== 'function') throw new Error('Callback must be a function')
	const newArray = []
	for (let i = 0; i < thisArg.length; i++) {
		newArray.push(callback(thisArg[i], i, thisArg))
	}
	return newArray
}