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1'use strict';
2// https://github.com/tc39/proposal-iterator-helpers
3var $ = require('../internals/export');
4var anObject = require('../internals/an-object');
5var toPositiveInteger = require('../internals/to-positive-integer');
6var createIteratorProxy = require('../internals/iterator-create-proxy');
7
8var IteratorProxy = createIteratorProxy(function (arg) {
9 var iterator = this.iterator;
10 var next = this.next;
11 var result, done;
12 while (this.remaining) {
13 this.remaining--;
14 result = anObject(next.call(iterator));
15 done = this.done = !!result.done;
16 if (done) return;
17 }
18 result = anObject(next.call(iterator, arg));
19 done = this.done = !!result.done;
20 if (!done) return result.value;
21});
22
23$({ target: 'Iterator', proto: true, real: true }, {
24 drop: function drop(limit) {
25 return new IteratorProxy({
26 iterator: anObject(this),
27 remaining: toPositiveInteger(limit)
28 });
29 }
30});