(p)
ttype : typedef
             | enum
             | struct
             | union
             | exception
             | service
ttype : typedef
             | enum
             | struct
             | union
             | exception
             | service
ttype : typedef | enum | struct | union | exception | service
def p_ttype(p):
    '''ttype : typedef
             | enum
             | struct
             | union
             | exception
             | service'''
def p_ttype ( p ) :