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