24 lines
773 B
JavaScript
24 lines
773 B
JavaScript
'use strict';
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var isArray = require('../internals/is-array');
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var isConstructor = require('../internals/is-constructor');
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var isObject = require('../internals/is-object');
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var wellKnownSymbol = require('../internals/well-known-symbol');
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var SPECIES = wellKnownSymbol('species');
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var $Array = Array;
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// a part of `ArraySpeciesCreate` abstract operation
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// https://tc39.es/ecma262/#sec-arrayspeciescreate
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module.exports = function (originalArray) {
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var C;
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if (isArray(originalArray)) {
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C = originalArray.constructor;
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// cross-realm fallback
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if (isConstructor(C) && (C === $Array || isArray(C.prototype))) C = undefined;
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else if (isObject(C)) {
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C = C[SPECIES];
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if (C === null) C = undefined;
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}
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} return C === undefined ? $Array : C;
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};
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