24 lines
727 B
JavaScript
24 lines
727 B
JavaScript
/* eslint-disable no-extend-native, func-names, space-before-function-paren, semi, space-infix-ops, max-len */
|
|
Array.prototype.first = function() {
|
|
return this[0];
|
|
}
|
|
|
|
Array.prototype.last = function() {
|
|
return this[this.length-1];
|
|
}
|
|
|
|
Array.prototype.find = Array.prototype.find || function(predicate, ...args) {
|
|
if (!this) throw new TypeError('Array.prototype.find called on null or undefined');
|
|
if (typeof predicate !== 'function') throw new TypeError('predicate must be a function');
|
|
|
|
const list = Object(this);
|
|
const thisArg = args[1];
|
|
let value = {};
|
|
|
|
for (let i = 0; i < list.length; i += 1) {
|
|
value = list[i];
|
|
if (predicate.call(thisArg, value, i, list)) return value;
|
|
}
|
|
|
|
return undefined;
|
|
};
|