OpenE2K/gcc
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

libstdc++: Fix miscellaneous issues with elements_view::_Sentinel [PR100631]

Browse Source 
libstdc++-v3/ChangeLog:

	PR libstdc++/100631
	* include/std/ranges (elements_view::_Iterator): Also befriend
	_Sentinel<!_Const>.
	(elements_view::_Sentinel::_M_equal): Templatize.
	(elements_view::_Sentinel::_M_distance_from): Split out from ...
	(elements_view::_Sentinel::operator-): ... here.  Depend on
	_Base2 instead of _Base in the return type.
	* testsuite/std/ranges/adaptors/elements.cc (test06, test07):
	New tests.
This commit is contained in:
Patrick Palka 2021-05-18 00:26:07 -04:00
parent a7ffc1ef6e
commit 2e2eef80ac
2 changed files with 43 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

18
libstdc++-v3/include/std/ranges
View File

@ -3634,16 +3634,22 @@ namespace views::__adaptor
requires sized_sentinel_for<iterator_t<_Base>, iterator_t<_Base>>
{ return __x._M_current - __y._M_current; }
friend _Sentinel<_Const>;
template <bool> friend struct _Sentinel;
};
template<bool _Const>
struct _Sentinel
{
private:
constexpr bool
_M_equal(const _Iterator<_Const>& __x) const
{ return __x._M_current == _M_end; }
template<bool _Const2>
constexpr bool
_M_equal(const _Iterator<_Const2>& __x) const
{ return __x._M_current == _M_end; }
template<bool _Const2>
constexpr auto
_M_distance_from(const _Iterator<_Const2>& __i) const
{ return _M_end - __i._M_current; }
using _Base = elements_view::_Base<_Const>;
sentinel_t<_Base> _M_end = sentinel_t<_Base>();
@ -3684,9 +3690,9 @@ namespace views::__adaptor
template<bool _Const2,
typename _Base2 = __detail::__maybe_const_t<_Const2, _Vp>>
requires sized_sentinel_for<sentinel_t<_Base>, iterator_t<_Base2>>
friend constexpr range_difference_t<_Base>
friend constexpr range_difference_t<_Base2>
operator-(const _Sentinel& __x, const _Iterator<_Const2>& __y)
{ return __x._M_end - __y._M_current; }
{ return __x._M_distance_from(__y); }
friend _Sentinel<!_Const>;
};

31
libstdc++-v3/testsuite/std/ranges/adaptors/elements.cc
View File

@ -115,6 +115,35 @@ test05()
VERIFY( r2[0] == 1 && r2[1] == 3 );
}
void
test06()
{
// PR libstdc++/100631
auto r = views::iota(0)
| views::filter([](int){ return true; })
| views::take(42)
| views::reverse
| views::transform([](int) { return std::make_pair(42, "hello"); })
| views::take(42)
| views::keys;
auto b = r.begin();
auto e = r.end();
e - b;
}
void
test07()
{
// PR libstdc++/100631 comment #2
auto r = views::iota(0)
| views::transform([](int) { return std::make_pair(42, "hello"); })
| views::keys;
auto b = ranges::cbegin(r);
auto e = ranges::end(r);
b.base() == e.base();
b == e;
}
int
main()
{
@ -123,4 +152,6 @@ main()
test03();
test04();
test05();
test06();
test07();
}