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