- enum identifier-opt < declaration-specifiers > { enumerator-list }
- enum identifier-opt < declaration-specifiers > { enumerator-list , }
- enum identifier < declaration-specifiers >
- enum identifier-opt < integer-constant > { enumerator-list }
- enum identifier-opt < integer-constant > { enumerator-list , }
- enum identifier < integer-constant >
+ enum identifier-opt : declaration-specifiers { enumerator-list }
+ enum identifier-opt : declaration-specifiers { enumerator-list , }