var error1 = new TypeError('Error 1'); var error2 = new TypeError('Error 2'); var aggregate = new AggregateError([error1, error2], 'Collected errors'); log(aggregate.errors[0] === error1); // => true log(aggregate.errors[1] === error2); // => true var cause = new TypeError('Something wrong'); var error = new TypeError('Here explained what`s wrong', { cause: cause }); log(error.cause === cause); // => true log(Error.prototype.toString.call({ message: 1, name: 2 }) === '2: 1'); // => true