anchor.diff:  UNION    : 'union';
   ENUM     : 'enum';
   
  +IF     : 'if';
  +ELSE   : 'else';
  +WHILE  : 'while';
  +FOR    : 'for';
  +SWITCH : 'switch';
  +
   COMMA : ',' ;
   STAR  : '*' ;
   SEMI  : ';' ;
  
positive.code:            -> ^(ENUM IDENT)
             ;
  
  notscope : ~(OPENBRA|CLOSEBRA) ;
  compoundStmt : OPENBRA notscope* (compoundStmt notscope*)* CLOSEBRA 
              -> ^(OPENBRA compoundStmt*) 
               ;
  
  
  
  
negative.code:    ;
  // GNU-c extensions that we simply want to ignore
  GNU : '__attribute' '__'? (' ' | '\t')* '((' ALPHA+ '))' REPLACEHIDDEN ;
  GNUEXPR: '({' (options {greedy=false;}:.)* '})' REPLACEHIDDEN ;
  
  ELLIPSIS : '...';
  ASSRIGHT : '>>=';
  