anchor.diff:    [t_number(), t_atom(), t_reference(), t_fun(), t_port(), t_pid(), t_tuple(),
      t_list(), t_binary()].
   
  +key_comparisons_fail(X0, KeyPos, TupleList) ->
  +  X = case t_is_number(t_inf(X0, t_number())) of
  +	false -> X0;
  +	true -> t_number()
  +      end,
  +  lists:all(fun(Tuple) ->
  +		Key = type(erlang, element, 2, [KeyPos, Tuple]),
  +		t_is_none(t_inf(Key, X))
  +	    end, TupleList).
   
   %%=============================================================================
   
  
positive.code: any_is_none_or_unit(Ts) ->
    lists:any(fun erl_types:t_is_none_or_unit/1, Ts).
  
  all_is_none(Ts) ->
    lists:all(fun erl_types:t_is_none/1, Ts).
  
  check_guard([X], Test, Type) ->
    check_guard_single(X, Test, Type).
  
  
negative.code: 		     case t_tuple_subtypes(Tuple) of
  		       unknown -> Ret;
  		       List ->
  			 case key_comparisons_fail(X, Y, List) of
  			   true -> t_atom('false');
  			   false -> Ret
  			 end
  