50 lines
2.0 KiB
JavaScript
50 lines
2.0 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 iteratorClose = require('../internals/iterator-close');
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var iteratorHelperThrowsOnInvalidIterator = require('../internals/iterator-helper-throws-on-invalid-iterator');
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var iteratorHelperWithoutClosingOnEarlyError = require('../internals/iterator-helper-without-closing-on-early-error');
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var IS_PURE = require('../internals/is-pure');
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var TAKE_WITHOUT_THROWING_ON_INVALID_ITERATOR = !IS_PURE && !iteratorHelperThrowsOnInvalidIterator('take', 1);
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var takeWithoutClosingOnEarlyError = !IS_PURE && !TAKE_WITHOUT_THROWING_ON_INVALID_ITERATOR
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&& iteratorHelperWithoutClosingOnEarlyError('take', RangeError);
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var FORCED = IS_PURE || TAKE_WITHOUT_THROWING_ON_INVALID_ITERATOR || takeWithoutClosingOnEarlyError;
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var IteratorProxy = createIteratorProxy(function () {
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var iterator = this.iterator;
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if (!this.remaining--) {
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this.done = true;
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return iteratorClose(iterator, 'normal', undefined);
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}
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var result = anObject(call(this.next, iterator));
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var done = this.done = !!result.done;
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if (!done) return result.value;
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});
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// `Iterator.prototype.take` method
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// https://tc39.es/ecma262/#sec-iterator.prototype.take
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$({ target: 'Iterator', proto: true, real: true, forced: FORCED }, {
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take: function take(limit) {
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anObject(this);
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var remaining;
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try {
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remaining = toPositiveInteger(notANaN(+limit));
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} catch (error) {
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iteratorClose(this, 'throw', error);
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}
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if (takeWithoutClosingOnEarlyError) return call(takeWithoutClosingOnEarlyError, this, remaining);
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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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