16 lines
606 B
JavaScript
16 lines
606 B
JavaScript
'use strict';
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var anObject = require('../internals/an-object');
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var aConstructor = require('../internals/a-constructor');
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var isNullOrUndefined = require('../internals/is-null-or-undefined');
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var wellKnownSymbol = require('../internals/well-known-symbol');
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var SPECIES = wellKnownSymbol('species');
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// `SpeciesConstructor` abstract operation
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// https://tc39.es/ecma262/#sec-speciesconstructor
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module.exports = function (O, defaultConstructor) {
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var C = anObject(O).constructor;
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var S;
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return C === undefined || isNullOrUndefined(S = anObject(C)[SPECIES]) ? defaultConstructor : aConstructor(S);
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};
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