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