anchor.diff:  private boolean inParens() { return !bracketStack.isEmpty() && bracketStack.peek() == LPAREN; }
   private boolean inCurly() { return !bracketStack.isEmpty() && bracketStack.peek() == LCURLY; }
   private boolean inSquare() { return !bracketStack.isEmpty() && bracketStack.peek() == LSQUARE; }
  +private boolean notInBrackets() { return bracketStack.isEmpty(); }
   }
   
   @lexer::header {
  
positive.code: 
  sep_stmt_list :
       t_FILLER? stmt_separator t_FILLER? (stmt t_FILLER?)*
    ;
  
  function_list :
  
negative.code:  * to be a column delimiter.
   */
  private boolean isElementSeparator() {
      if(!(notInBrackets() || inCurly() || inSquare())) {
          return false;
      }
      Token prevToken = input.LT(-1);
  