On Thu, 21 Oct 2021 at 15:41, Patrick Palka via Libstdc++ <
libstd...@gcc.gnu.org> wrote:
> Tested on x86_64-pc-linux-gnu, does this look OK for trunk/11/10?
>
Yes for trunk.
I'm undecided whether we want to make this breaking change on the branches.
> libstdc++-v3/ChangeLog:
>
> * include/std/ranges (istream_view): Replace this function
> template with an alias template as per P2432R1.
> (wistream_view): Define as per P2432R1.
> (views::_Istream, views::istream): Likewise.
> * testsuite/std/ranges/istream_view.cc (test07): New test.
> ---
> libstdc++-v3/include/std/ranges | 25 ++++++++++++++++---
> .../testsuite/std/ranges/istream_view.cc | 13 ++++++++++
> 2 files changed, 34 insertions(+), 4 deletions(-)
>
> diff --git a/libstdc++-v3/include/std/ranges
> b/libstdc++-v3/include/std/ranges
> index 30ba0606869..7aa0f9dfc67 100644
> --- a/libstdc++-v3/include/std/ranges
> +++ b/libstdc++-v3/include/std/ranges
> @@ -781,10 +781,27 @@ namespace views
> friend _Iterator;
> };
>
> - template<typename _Val, typename _CharT, typename _Traits>
> - basic_istream_view<_Val, _CharT, _Traits>
> - istream_view(basic_istream<_CharT, _Traits>& __s)
> - { return basic_istream_view<_Val, _CharT, _Traits>{__s}; }
> + template<typename _Val>
> + using istream_view = basic_istream_view<_Val, char>;
> +
> + template<typename _Val>
> + using wistream_view = basic_istream_view<_Val, wchar_t>;
> +
> +namespace views
> +{
> + template<typename _Tp>
> + struct _Istream
> + {
> + template<typename _CharT, typename _TraitsT>
> + [[nodiscard]]
> + constexpr auto
> + operator()(basic_istream<_CharT, _TraitsT>& __e) const
> + { return basic_istream_view<_Tp, _CharT, _TraitsT>(__e); }
> + };
> +
> + template<typename _Tp>
> + inline constexpr _Istream<_Tp> istream;
> +}
>
> // C++20 24.7 [range.adaptors] Range adaptors
>
> diff --git a/libstdc++-v3/testsuite/std/ranges/istream_view.cc
> b/libstdc++-v3/testsuite/std/ranges/istream_view.cc
> index f5c0c2a6bb0..ea7c5a35ef7 100644
> --- a/libstdc++-v3/testsuite/std/ranges/istream_view.cc
> +++ b/libstdc++-v3/testsuite/std/ranges/istream_view.cc
> @@ -103,6 +103,18 @@ test06()
> static_assert( std::is_same_v<V, W> );
> }
>
> +void
> +test07()
> +{
> + // P2432R1, views::istream
> + auto nums = std::istringstream("0 1 2 3 4");
> + ranges::istream_view<int> v(nums);
> + int sum = 0;
> + for (int val : views::istream<int>(nums))
> + sum += val;
> + VERIFY( sum == 10 );
> +}
> +
> int
> main()
> {
> @@ -112,4 +124,5 @@ main()
> test04();
> test05();
> test06();
> + test07();
> }
> --
> 2.33.1.711.g9d530dc002
>
>
