anchor.diff:  t_COLON : COLON { offsetTracker.advanceInLine(1); };
   t_AT : AT { offsetTracker.advanceInLine(1); };
   
  +t_ASSIGN : ASSIGN { offsetTracker.advanceInLine(1); };
  +
   t_LPAREN : LPAREN { offsetTracker.advanceInLine(1); bracketStack.push(LPAREN); };
   t_RPAREN : RPAREN { offsetTracker.advanceInLine(1); bracketStack.pop(); };
   t_LCURLY : LCURLY { offsetTracker.advanceInLine(1); bracketStack.push(LCURLY); };
  
positive.code: colon_expr :
       plus_expr (t_FILLER? t_COLON t_FILLER? plus_expr (t_FILLER? t_COLON t_FILLER? plus_expr)?)?
    ;
  
  plus_expr :
       binary_expr (t_FILLER? (t_PLUS | t_MINUS) t_FILLER? binary_expr)*
    ;
  
negative.code: t_BRACKET_COMMENT : BRACKET_COMMENT { offsetTracker.advanceByTextSize($text); };
  t_COMMENT : COMMENT { offsetTracker.advanceByTextSize($text); };
  
  t_SHELL_COMMAND : SHELL_COMMAND { offsetTracker.advanceByTextSize($text); };
  
  t_FILLER : FILLER { offsetTracker.advanceByTextSize($text); };
  
  t_LINE_TERMINATOR : LINE_TERMINATOR { offsetTracker.advanceToNewLine(1, 1); };
  