anchor.diff:  literal
       : NATURALLITERAL
       | FLOATLITERAL
  -    | CHARLITERAL
  -    | DATELITERAL
  -    | TIMELITERAL
  -    | REGEXPLITERAL
  +    | QUOTEDLITERAL
       | stringLiteral
       ;   
   
  
positive.code: 
  compilationUnit
      : (importDeclaration)*
        (annotations? toplevelDeclaration)+
        EOF
      ;
      
  toplevelDeclaration
      : classDeclaration 
      | interfaceDeclaration 
      //| converterDeclaration 
      //| decoratorDeclaration
      | aliasDeclaration
      ;
  
  
negative.code:     ;
  
  methodExpression
      : implicationExpression undelimitedNamedArgument*
      ;
  
  undelimitedNamedArgument
      : ( memberName | 'case' '(' expressions ')' ) 
        undelimitedNamedArgumentDefinition 
      ;
  
  implicationExpression
  