25 lines
1020 B
JavaScript
25 lines
1020 B
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 toObject = require('../internals/to-object');
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var isPrototypeOf = require('../internals/object-is-prototype-of');
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var IteratorPrototype = require('../internals/iterators-core').IteratorPrototype;
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var createIteratorProxy = require('../internals/iterator-create-proxy');
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var getIteratorFlattenable = require('../internals/get-iterator-flattenable');
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var IS_PURE = require('../internals/is-pure');
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var IteratorProxy = createIteratorProxy(function () {
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return call(this.next, this.iterator);
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}, true);
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// `Iterator.from` method
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// https://github.com/tc39/proposal-iterator-helpers
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$({ target: 'Iterator', stat: true, forced: IS_PURE }, {
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from: function from(O) {
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var iteratorRecord = getIteratorFlattenable(typeof O == 'string' ? toObject(O) : O, true);
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return isPrototypeOf(IteratorPrototype, iteratorRecord.iterator)
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? iteratorRecord.iterator
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: new IteratorProxy(iteratorRecord);
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}
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});
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