interfaceDeclaration:
     'interface' Identifier ';'
   | 'interface' Identifier (':' baseClassList)? structBody
   | 'interface' Identifier templateParameters constraint? (structBody | ';')
   | 'interface' Identifier templateParameters constraint? (':' baseClassList)? structBody
   | 'interface' Identifier templateParameters (':' baseClassList)? constraint? structBody
   ;