--- /dev/null
+'use strict';
+// https://github.com/tc39/proposal-iterator-helpers
+var $ = require('../internals/export');
+var anObject = require('../internals/an-object');
+var toPositiveInteger = require('../internals/to-positive-integer');
+var createIteratorProxy = require('../internals/iterator-create-proxy');
+
+var IteratorProxy = createIteratorProxy(function (arg) {
+ var iterator = this.iterator;
+ var next = this.next;
+ var result, done;
+ while (this.remaining) {
+ this.remaining--;
+ result = anObject(next.call(iterator));
+ done = this.done = !!result.done;
+ if (done) return;
+ }
+ result = anObject(next.call(iterator, arg));
+ done = this.done = !!result.done;
+ if (!done) return result.value;
+});
+
+$({ target: 'Iterator', proto: true, real: true }, {
+ drop: function drop(limit) {
+ return new IteratorProxy({
+ iterator: anObject(this),
+ remaining: toPositiveInteger(limit)
+ });
+ }
+});