DownCaster(failureHandler: AnyTypeTransformation.TypeTransformationFailureHandler<T, TSub>)
Helps to make an assertion about the BaseAssertionPlant.subject, that it is of type T and can be down-casted to type TSub.
failureHandler - The handler which deals with a lambda function which could have created subsequent assertions
for a down-casted subject.
Constructor
Helps to make an assertion about the BaseAssertionPlant.subject, that it is of type T and can be
down-casted to type TSub.