anchor.diff:    [New|Terminators];
   
   handle_terminator({ E, _ }, [{ S, _ }|Terminators]) when
  +    S == 'do', E == 'end';
  +    S == 'fn', E == 'end';
       S == '(',  E == ')';
       S == '[',  E == ']';
       S == '{',  E == '}';
  
positive.code:   Terminators;
  
  handle_terminator({ E, Line }, _) when
      E == ')';
      E == ']';
      E == '}';
  
negative.code: handle_terminator(_, Terminators) ->
    Terminators.
  
  terminator('fn') -> 'end';
  terminator('do') -> 'end';
  terminator('(')  -> ')';
  terminator('[')  -> ']';
  terminator('{')  -> '}';
  terminator('<<') -> '>>'.
  
  % Keywords check
  keyword(Line, paren_identifier, fn, Tokens) ->
    [{ 'fn_paren', Line }|Tokens];
  
  