2 // https://github.com/tc39/proposal-iterator-helpers
3 var $ = require('../internals/export');
4 var apply = require('../internals/function-apply');
5 var anObject = require('../internals/an-object');
6 var toPositiveInteger = require('../internals/to-positive-integer');
7 var createAsyncIteratorProxy = require('../internals/async-iterator-create-proxy');
9 var AsyncIteratorProxy = createAsyncIteratorProxy(function (Promise, args) {
12 return new Promise(function (resolve, reject) {
13 var loop = function () {
16 anObject(apply(state.next, state.iterator, state.remaining ? [] : args))
17 ).then(function (step) {
19 if (anObject(step).done) {
21 resolve({ done: true, value: undefined });
22 } else if (state.remaining) {
25 } else resolve({ done: false, value: step.value });
26 } catch (err) { reject(err); }
28 } catch (error) { reject(error); }
35 $({ target: 'AsyncIterator', proto: true, real: true }, {
36 drop: function drop(limit) {
37 return new AsyncIteratorProxy({
38 iterator: anObject(this),
39 remaining: toPositiveInteger(limit)