base-clause: : base-specifier-list
base-specifier-list: base-specifier ... base-specifier-list , base-specifier ...
base-specifier: attribute-specifier-seq class-or-decltype attribute-specifier-seq virtual access-specifier class-or-decltype attribute-specifier-seq access-specifier virtual class-or-decltype
class-or-decltype: nested-name-specifier class-name nested-name-specifier template simple-template-id decltype-specifier
access-specifier: private protected public