| //===----------------------------------------------------------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| // UNSUPPORTED: c++03, c++11, c++14, c++17, c++20 |
| |
| // std::ranges::range_adaptor_closure; |
| |
| #include <ranges> |
| |
| #include <algorithm> |
| #include <vector> |
| |
| #include "test_range.h" |
| |
| template <class T> |
| concept CanDeriveFromRangeAdaptorClosure = requires { typename std::ranges::range_adaptor_closure<T>; }; |
| static_assert(!CanDeriveFromRangeAdaptorClosure<int>); |
| |
| struct Foo {}; |
| static_assert(CanDeriveFromRangeAdaptorClosure<Foo>); |
| static_assert(!CanDeriveFromRangeAdaptorClosure<Foo&>); |
| static_assert(!CanDeriveFromRangeAdaptorClosure<const Foo>); |
| static_assert(!CanDeriveFromRangeAdaptorClosure<volatile Foo>); |
| static_assert(!CanDeriveFromRangeAdaptorClosure<const volatile Foo&&>); |
| |
| struct incomplete_t; |
| static_assert(CanDeriveFromRangeAdaptorClosure<incomplete_t>); |
| |
| using range_t = std::vector<int>; |
| |
| template <class T> |
| concept RangeAdaptorClosure = |
| CanBePiped<range_t, T&> && CanBePiped<range_t, const T&> && CanBePiped<range_t, T&&> && |
| CanBePiped<range_t, const T&&>; |
| |
| struct callable : std::ranges::range_adaptor_closure<callable> { |
| static void operator()(const range_t&) {} |
| }; |
| static_assert(RangeAdaptorClosure<callable>); |
| |
| // `not_callable_1` doesn't have an `operator()` |
| struct not_callable_1 : std::ranges::range_adaptor_closure<not_callable_1> {}; |
| static_assert(!RangeAdaptorClosure<not_callable_1>); |
| |
| // `not_callable_2` doesn't have an `operator()` that accepts a `range` argument |
| struct not_callable_2 : std::ranges::range_adaptor_closure<not_callable_2> { |
| static void operator()() {} |
| }; |
| static_assert(!RangeAdaptorClosure<not_callable_2>); |
| |
| // `not_derived_from_1` doesn't derive from `std::ranges::range_adaptor_closure` |
| struct not_derived_from_1 { |
| static void operator()(const range_t&) {} |
| }; |
| static_assert(!RangeAdaptorClosure<not_derived_from_1>); |
| |
| // `not_derived_from_2` doesn't publicly derive from `std::ranges::range_adaptor_closure` |
| struct not_derived_from_2 : private std::ranges::range_adaptor_closure<not_derived_from_2> { |
| static void operator()(const range_t&) {} |
| }; |
| static_assert(!RangeAdaptorClosure<not_derived_from_2>); |
| |
| // `not_derived_from_3` doesn't derive from the correct specialization of `std::ranges::range_adaptor_closure` |
| struct not_derived_from_3 : std::ranges::range_adaptor_closure<callable> { |
| static void operator()(const range_t&) {} |
| }; |
| static_assert(!RangeAdaptorClosure<not_derived_from_3>); |
| |
| // `not_derived_from_4` doesn't derive from exactly one specialization of `std::ranges::range_adaptor_closure` |
| struct not_derived_from_4 |
| : std::ranges::range_adaptor_closure<not_derived_from_4>, |
| std::ranges::range_adaptor_closure<callable> { |
| static void operator()(const range_t&) {} |
| }; |
| static_assert(!RangeAdaptorClosure<not_derived_from_4>); |
| |
| // `is_range` models `range` |
| struct is_range : std::ranges::range_adaptor_closure<is_range> { |
| static void operator()(const range_t&) {} |
| int* begin() const { return nullptr; } |
| int* end() const { return nullptr; } |
| }; |
| static_assert(std::ranges::range<is_range> && std::ranges::range<const is_range>); |
| static_assert(!RangeAdaptorClosure<is_range>); |
| |
| // user-defined range adaptor closure object |
| struct negate_fn : std::ranges::range_adaptor_closure<negate_fn> { |
| template <std::ranges::range Range> |
| static constexpr decltype(auto) operator()(Range&& range) { |
| return std::forward<Range>(range) | std::views::transform([](auto element) { return -element; }); |
| } |
| }; |
| static_assert(RangeAdaptorClosure<negate_fn>); |
| constexpr auto negate = negate_fn{}; |
| |
| // user-defined range adaptor closure object |
| struct plus_1_fn : std::ranges::range_adaptor_closure<plus_1_fn> { |
| template <std::ranges::range Range> |
| static constexpr decltype(auto) operator()(Range&& range) { |
| return std::forward<Range>(range) | std::views::transform([](auto element) { return element + 1; }); |
| } |
| }; |
| static_assert(RangeAdaptorClosure<plus_1_fn>); |
| constexpr auto plus_1 = plus_1_fn{}; |
| |
| constexpr bool test() { |
| const std::vector<int> n{1, 2, 3, 4, 5}; |
| const std::vector<int> n_negate{-1, -2, -3, -4, -5}; |
| |
| assert(std::ranges::equal(n | negate, n_negate)); |
| assert(std::ranges::equal(negate(n), n_negate)); |
| |
| assert(std::ranges::equal(n | negate | negate, n)); |
| assert(std::ranges::equal(n | (negate | negate), n)); |
| assert(std::ranges::equal((n | negate) | negate, n)); |
| assert(std::ranges::equal(negate(n) | negate, n)); |
| assert(std::ranges::equal(negate(n | negate), n)); |
| assert(std::ranges::equal((negate | negate)(n), n)); |
| assert(std::ranges::equal(negate(negate(n)), n)); |
| |
| const std::vector<int> n_plus_1_negate{-2, -3, -4, -5, -6}; |
| assert(std::ranges::equal(n | plus_1 | negate, n_plus_1_negate)); |
| assert(std::ranges::equal( |
| n | plus_1 | std::views::transform([](auto element) { return element; }) | negate, n_plus_1_negate)); |
| |
| const std::vector<int> n_negate_plus_1{0, -1, -2, -3, -4}; |
| assert(std::ranges::equal(n | negate | plus_1, n_negate_plus_1)); |
| assert(std::ranges::equal(n | std::views::reverse | negate | plus_1 | std::views::reverse, n_negate_plus_1)); |
| return true; |
| } |
| |
| int main(int, char**) { |
| test(); |
| static_assert(test()); |
| |
| return 0; |
| } |