14 lines
516 B
JavaScript
14 lines
516 B
JavaScript
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var anObject = require('../internals/an-object');
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var aFunction = require('../internals/a-function');
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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.github.io/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 || (S = anObject(C)[SPECIES]) == undefined ? defaultConstructor : aFunction(S);
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};
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