Demeter_in = <input> Input.                                                
Input :                                                                    
  Cd_graph                                                                 
    *common*.                                                              
Ll1SetElement = [<token> DemString] [<empty> TEpsilon]                        
                [<terminal> TClassTerminal]                                
                [<eof> TEndOfFile].                                        

Cd_graph = < adjacencies > Nlist(Adjacency)                                
           [ "*dfs_n*" <dfs_n> DemNumber ]                                             
           [ "*current_component*" <current_component> DemNumber ]                     
           .                                                                        
Vertices_With_Same_Fset = "*pool*" <pool> List(Vertex).                    
Adjacency =                                                                
  < source > Vertex                                                        
  ["(" < parameters> Comma_list(Vertex) ")"]                               
  < ns > Neighbors                                                         
  ["*treated*" <treated> DemNumber]                                           
  ["*imm_ancester*" <imm_ancester> Vertex ]                                
  ["*inherited_Any_vertex*" <inherited_Any_vertex> List(Any_vertex) ]      
  ["*expanded_common_parts*" <expanded_common_parts> List(Common_parts) ]  
  ["*associated*" <associated> List(Adjacency) "." ]  
  [ "*dfs*"   <dfs>   DemNumber ]                                             
  [ "*high*"  <high>  DemNumber ]                                             
  [ "*scc*"   <scc>   DemNumber ]                                             
  [ "( firstset" <firstset> Comma_list(Ll1SetElement) ")"]                  
  [ "( followset" <followset> Comma_list(Ll1SetElement) ")"]                
  "." .                                                                    
Common_parts = "*common parts*" <owner> Adjacency   "*is*"
                                <common> List(Any_vertex).                 
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]
  ["*emptycommon*" <emptycommon> DemNumber].
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* [ "*origin*" <origin> Adjacency "." ].
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
                 ["*adjacency*" <adjacency> Adjacency "." ]                                    
                 ["(" <actual_parameters> Comma_list(Term) ")" ]                          
                 [ "(firstset" <firstset> Comma_list(Ll1SetElement) ")"]                  
                 [ "(followset" <followset> Comma_list(Ll1SetElement) ")"] .

CppTerm = "$" .

Normal = .

TermRef : LocalRef | ModuleRef.

ModuleRef : CompRef | LibRef *common* <moduleName> DemIdent.

LocalRef = .
CompRef = "@".
LibRef  = "@@".

Optional_term = "[" <opt> Sandwich(Opt_labeled_term) "]".                  
TEpsilon = "*epsilon*" .                                                   
TEndOfFile = "*eof*" .                                                     
TClassTerminal = "*classterminal*" <terminalName> DemIdent .                  

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)                                             
  [ "(  firstset" <firstset> Comma_list(Ll1SetElement) ")"]                  
  [ "(  followset" <followset> Comma_list(Ll1SetElement) ")"]                
  .