- Plain =
          
        
 
        %i[number]
 
      
        - NumberRef =
          
        
 
        %i[number_ref number_rel_ref]
 
      
        - Number =
          
        
 
        Plain + NumberRef
 
      
        - Name =
          
        
 
        %i[name_ref]
 
      
        - RecursionLevel =
          
        
 
        %i[name_recursion_ref number_recursion_ref]
 
      
        - V1_8_6 =
          
        
 
        Plain
 
      
        - V1_9_1 =
          
        
 
        Name + NumberRef + RecursionLevel
 
      
        - All =
          
        
 
        V1_8_6 + V1_9_1
 
      
        - Type =
          
        
 
        :backref