Demeter_in = <input> Input.                                                
Input :                                                                    
  Cd_graph                                                                 
    *common*.                                                              
Cd_graph = < adjacencies > nlist(Adjacency)                                
  ["*terminal_sets*" <terminal_sets> comma_list(Vertex) "."]               
  .                                                                        
Adjacency =                                                                
  < source > Vertex                                                        
  ["(" < parameters> comma_list(Vertex) ")"]                               
  < ns > Neighbors                                                         
  "." .                                                                    
Neighbors :                                                                
  Neighbors_wc |                                                           
  Repetit_n                                                                
  *common*.                                                                
Neighbors_wc :                                                             
  Construct_ns |                                                           
  Alternat_ns                                                              
  *common* < construct_ns > list(Any_vertex).                              
Construct_ns = "=".                                                        
Alternat_ns = ":"                                                          
  < alternat_ns > bar_list(Term) [<common> Common].                        
Common = "*common*".                                                       
Repetit_n = "~" <sandwiched> Sandwich(Kernel).                             
Kernel = [ <nonempty> Term ]                                               
  "{" <repeated> Sandwich(Term) "}".                                       
Any_vertex :                                                               
  Opt_labeled_term                                                         
  | Optional_term                                                          
  | Syntax_vertex                                                          
  | Inherit_term                                                           
  *common*.                                                                
Vertex = < vertex_name > DemIdent .                                           
Syntax_vertex :                                                            
  Regular_syntax                                                           
  | Print_command                                                          
  *common*.                                                                
Regular_syntax  = < string > DemString .                                      
Print_command :                                                            
  Print_indent | Print_unindent | Print_skip | Print_space *common*.       
Print_indent = "+" .                                                       
Print_unindent = "-" .                                                     
Print_skip = "*l" .                                                        
Print_space = "*s" .                                                       
Opt_labeled_term :                                                         
  Labeled                                                                  
  | Regular                                                                
    *common* [StaticSpec] [AccessorSpec] <vertex> Term.
StaticSpec = "*static*" .
AccessorSpec : ReadOnlyAcc | PrivateAcc *common* .
ReadOnlyAcc = "*read-only*" .
PrivateAcc = "*private*" .
Regular = .                                                                
Labeled = "<" < label_name > DemIdent ">" .                                   
Inherit_term = "*inherit*" <inherited> comma_list(Term).                   
Term :                                                                     
  Normal | CppTerm 
  *common* <vertex> Vertex                                               
	   <moduleRef> TermRef
	   ["(" <actual_parameters> comma_list(Term) ")" ] .

CppTerm = "$" .
TermRef : LocalRef | ModuleRef.
ModuleRef : CompRef | LibRef *common* <moduleName> DemIdent.
LocalRef = .
CompRef = "@".
LibRef  = "@@".
Normal = .                                                                 
Optional_term = "[" <opt> Sandwich(Opt_labeled_term) "]".                  

list(S) ~ {S}.                                                             
nlist(S) ~ S {S}.                                                          
bar_list(S) ~ S {"|" S}.                                                   
comma_list(S) ~ S {"," S}.                                                 
Sandwich(S) =                                                              
  <first> list(Syntax_vertex) <inner> S                                    
  <second> list(Syntax_vertex).                                            



Lc = < labelname > DemIdent
     < classname > DemIdent.

Item_set = < item > Lc
           <cardinality> DemNumber
           <members> list( DemIdent ).

Set_of_item_sets =
              < biggestcardinallity > DemNumber
              < itemsets > list ( Item_set ).

Belongs_to_set =
               < classname > DemIdent
               < cardinality > DemNumber
               < belogsto > list(Lc).

Set_of_belongs_to_sets =
               < belongstosets > list( Belongs_to_set ).

Tree_structure =
                < item > Lc
                < contains > Lc
                < iscontained > Lc .

Set_of_tree_structures =
                < treestructures > list( Tree_structure ).

Inheritanceentry =
	<symbolname>DemIdent
	<numofsuper>DemNumber
	<superclasses> list(Term).

Inheritancereport =
	<inheritancelist> list(Inheritanceentry).