2 REM ExpectedError: BC31088
3 REM ErrorMessage: 'NotOverridable' cannot be specified for methods that do not override another method.
6 REM ExpectedError: BC40005
7 REM ErrorMessage: sub 'F1' shadows an overridable method in a base class. To override the base method, this method must be declared 'Overrides'.
10 Public Overridable Sub F1()
16 Public NotOverridable Sub F1()