21 lines
721 B
JavaScript
21 lines
721 B
JavaScript
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var isObject = require('../internals/is-object');
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var isArray = require('../internals/is-array');
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var wellKnownSymbol = require('../internals/well-known-symbol');
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var SPECIES = wellKnownSymbol('species');
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// `ArraySpeciesCreate` abstract operation
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// https://tc39.github.io/ecma262/#sec-arrayspeciescreate
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module.exports = function (originalArray, length) {
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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 (typeof C == 'function' && (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 new (C === undefined ? Array : C)(length === 0 ? 0 : length);
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};
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