2 // https://github.com/tc39/proposal-iterator-helpers
3 var $ = require('../internals/export');
4 var apply = require('../internals/function-apply');
5 var call = require('../internals/function-call');
6 var anObject = require('../internals/an-object');
7 var toPositiveInteger = require('../internals/to-positive-integer');
8 var createAsyncIteratorProxy = require('../internals/async-iterator-create-proxy');
10 var AsyncIteratorProxy = createAsyncIteratorProxy(function (Promise, args) {
11 var iterator = this.iterator;
12 var returnMethod, result;
13 if (!this.remaining--) {
14 result = { done: true, value: undefined };
16 returnMethod = iterator['return'];
17 if (returnMethod !== undefined) {
18 return Promise.resolve(call(returnMethod, iterator)).then(function () {
23 } return apply(this.next, iterator, args);
26 $({ target: 'AsyncIterator', proto: true, real: true }, {
27 take: function take(limit) {
28 return new AsyncIteratorProxy({
29 iterator: anObject(this),
30 remaining: toPositiveInteger(limit)