anchor.diff:      : IDENTIFIER | IDENTIFIER '=' IDENTIFIER
       ;
   
  -block_type:('void'|'id'|IDENTIFIER) '(''^' IDENTIFIER? ')' block_parameters? ;
  +block_type:type_specifier '(''^' type_specifier? ')' block_parameters? ;
   
   type_specifier:
   'void' | 'char' | 'short' | 'int' | 'long' | 'float' | 'double' | 'signed' | 'unsigned' 
  
positive.code:          postfix_expression':'postfix_expression;
  
  dictionary_expression:
          '@''{' dictionary_pair? (',' dictionary_pair)* '}';
  
  array_expression:
          '@''[' postfix_expression? (',' postfix_expression)* ']';
  
  box_expression:
          '@''('postfix_expression')' |
  
negative.code:   | 'NS_ENUM' '(' type_name ',' identifier ')' '{' enumerator_list '}' ;
  
  
  enumerator_list : enumerator (',' enumerator)* ','? ;
  enumerator : identifier ('=' constant_expression)?;
  
  pointer
  