37 lines
1.2 KiB
JavaScript
37 lines
1.2 KiB
JavaScript
'use strict';
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var $ = require('../internals/export');
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var call = require('../internals/function-call');
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var anObject = require('../internals/an-object');
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var getIteratorDirect = require('../internals/get-iterator-direct');
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var notANaN = require('../internals/not-a-nan');
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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 IS_PURE = require('../internals/is-pure');
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var IteratorProxy = createIteratorProxy(function () {
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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(call(next, 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(call(next, iterator));
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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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// `Iterator.prototype.drop` method
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// https://github.com/tc39/proposal-iterator-helpers
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$({ target: 'Iterator', proto: true, real: true, forced: IS_PURE }, {
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drop: function drop(limit) {
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anObject(this);
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var remaining = toPositiveInteger(notANaN(+limit));
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return new IteratorProxy(getIteratorDirect(this), {
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remaining: remaining
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});
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}
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});
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