如果 module.status'errored',则该属性包含模块在求值过程中抛出的异常。 如果状态是别的,访问这个属性会导致抛出异常。

    If the module.status is 'errored', this property contains the exception thrown by the module during evaluation. If the status is anything else, accessing this property will result in a thrown exception.

    The value undefined cannot be used for cases where there is not a thrown exception due to possible ambiguity with throw undefined;.

    Corresponds to the [[EvaluationError]] field of Cyclic Module Records in the ECMAScript specification.