anchor.diff:  %-define(DEBUG, true).
   
   -ifdef(DEBUG).
  +-define(FORM_TEST(T),
  +        _ = case T of
  +                {eof, _Line} -> ok;
  +                {warning, _W} -> ok;
  +                {error, _E} -> ok;
  +                _ -> ?TEST(T)
  +            end).
  +-define(EXPRS_TEST(L),
  +        [?TEST(E) || E <- L]).
   -define(TEST(T),
           %% Assumes that erl_anno has been compiled with DEBUG=true.
           %% erl_pp does not use the annoations, but test it anyway.
  
positive.code:                     erlang:error(badarg, [T])
              end).
  -else.
  -define(TEST(T), ok).
  -endif.
  
  
negative.code:       Options :: options()).
  
  exprs(Es, I, Options) ->
      ?EXPRS_TEST(Es),
      frmt({seq,[],[],[$,],lexprs(Es, options(Options))}, I, state(Options)).
  
  -spec(expr(Expression) -> io_lib:chars() when
  