diff options
| -rw-r--r-- | libstdc++-v3/ChangeLog | 6 | ||||
| -rw-r--r-- | libstdc++-v3/include/std/ranges | 2 | ||||
| -rw-r--r-- | libstdc++-v3/testsuite/std/ranges/adaptors/lwg3325_neg.cc | 35 |
3 files changed, 43 insertions, 0 deletions
diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog index 1bb2f3d..66c319d 100644 --- a/libstdc++-v3/ChangeLog +++ b/libstdc++-v3/ChangeLog @@ -1,5 +1,11 @@ 2020-02-25 Patrick Palka <ppalka@redhat.com> + LWG 3325 Constrain return type of transformation function for + transform_view + * include/std/ranges (transform_view): Constrain the return type of the + transformation function as per LWG 3325. + * testsuite/std/ranges/adaptors/lwg3325_neg.cc: New test. + LWG 3313 join_view::_Iterator::operator-- is incorrectly constrained * include/std/ranges (join_view::_Iterator::operator--): Require that range_reference_t<_Base> models common_range. diff --git a/libstdc++-v3/include/std/ranges b/libstdc++-v3/include/std/ranges index ffdd336..442d1d0 100644 --- a/libstdc++-v3/include/std/ranges +++ b/libstdc++-v3/include/std/ranges @@ -1540,6 +1540,8 @@ namespace views template<input_range _Vp, copy_constructible _Fp> requires view<_Vp> && is_object_v<_Fp> && regular_invocable<_Fp&, range_reference_t<_Vp>> + && std::__detail::__can_reference<invoke_result_t<_Fp&, + range_reference_t<_Vp>>> class transform_view : public view_interface<transform_view<_Vp, _Fp>> { private: diff --git a/libstdc++-v3/testsuite/std/ranges/adaptors/lwg3325_neg.cc b/libstdc++-v3/testsuite/std/ranges/adaptors/lwg3325_neg.cc new file mode 100644 index 0000000..ac17471 --- /dev/null +++ b/libstdc++-v3/testsuite/std/ranges/adaptors/lwg3325_neg.cc @@ -0,0 +1,35 @@ +// Copyright (C) 2020 Free Software Foundation, Inc. +// +// This file is part of the GNU ISO C++ Library. This library is free +// software; you can redistribute it and/or modify it under the +// terms of the GNU General Public License as published by the +// Free Software Foundation; either version 3, or (at your option) +// any later version. + +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU General Public License for more details. + +// You should have received a copy of the GNU General Public License along +// with this library; see the file COPYING3. If not see +// <http://www.gnu.org/licenses/>. + +// { dg-options "-std=gnu++2a" } +// { dg-do compile { target c++2a } } + +#include <ranges> + +namespace ranges = std::ranges; +namespace views = std::views; + +void +test01() +{ + auto f = [] (int x) { }; + int x[] = {1}; + auto v = ranges::transform_view{x, f}; // { dg-error "deduction failed|no match" } +} + +// { dg-prune-output "constraint failure" } +// { dg-prune-output "in requirements" } |