On Wed, 26 May 2021, Tim Song wrote:
> I noticed that output_iterator_wrapper still has a (non-void)
> value_type. Perhaps we can get better coverage if it doesn't have one?
> The existing tests should have caught this case with that change, at least.
Good point, and I guess it should be fine to make its pointer and
reference void as well. I'm testing:
--- a/libstdc++-v3/testsuite/util/testsuite_iterators.h
+++ b/libstdc++-v3/testsuite/util/testsuite_iterators.h
@@ -122,7 +122,7 @@ namespace __gnu_test
*/
template<class T>
struct output_iterator_wrapper
- : public std::iterator<std::output_iterator_tag, T, std::ptrdiff_t, T*, T&>
+ : public std::iterator<std::output_iterator_tag, void, std::ptrdiff_t, void,
void>
{
protected:
output_iterator_wrapper() : ptr(0), SharedInfo(0)
>
> On Wed, May 26, 2021 at 12:00 PM Patrick Palka via Libstdc++
> <libstd...@gcc.gnu.org> wrote:
> >
> > - else if constexpr (input_iterator<_Out>
> > - && same_as<iter_value_t<_Iter>,
> > iter_value_t<_Out>>)
> > + else if constexpr (requires { requires (input_iterator<_Out>
> > + &&
> > same_as<iter_value_t<_Iter>,
> > +
> > iter_value_t<_Out>>); })
>
> It's arguably cleaner to extract this into a concept which can then
> also be used in the constraint.
Sounds good, though I'm not sure what name to give to this relatively
ad-hoc set of requirements. Any suggestions? :)
