79 lines · cpp
1//===----------------------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9// UNSUPPORTED: c++03, c++11, c++14, c++1710 11// template<class I1, class I2>12// concept indirectly_swappable;13 14#include <iterator>15 16#include "test_macros.h"17 18template<class T, class ValueType = T>19struct PointerTo {20 using value_type = ValueType;21 T& operator*() const;22};23 24static_assert(std::indirectly_swappable<PointerTo<int>>);25static_assert(std::indirectly_swappable<PointerTo<int>, PointerTo<int>>);26 27struct B;28 29struct A {30 friend void iter_swap(const PointerTo<A>&, const PointerTo<A>&);31};32 33// Is indirectly swappable.34struct B {35 friend void iter_swap(const PointerTo<B>&, const PointerTo<B>&);36 friend void iter_swap(const PointerTo<A>&, const PointerTo<B>&);37 friend void iter_swap(const PointerTo<B>&, const PointerTo<A>&);38};39 40// Valid except ranges::iter_swap(i2, i1).41struct C {42 friend void iter_swap(const PointerTo<C>&, const PointerTo<C>&);43 friend void iter_swap(const PointerTo<A>&, const PointerTo<C>&);44 friend void iter_swap(const PointerTo<C>&, const PointerTo<A>&) = delete;45};46 47// Valid except ranges::iter_swap(i1, i2).48struct D {49 friend void iter_swap(const PointerTo<D>&, const PointerTo<D>&);50 friend void iter_swap(const PointerTo<A>&, const PointerTo<D>&) = delete;51 friend void iter_swap(const PointerTo<D>&, const PointerTo<A>&);52};53 54// Valid except ranges::iter_swap(i2, i2).55struct E {56 E operator=(const E&) = delete;57 friend void iter_swap(const PointerTo<E>&, const PointerTo<E>&) = delete;58 friend void iter_swap(const PointerTo<A>&, const PointerTo<E>&);59 friend void iter_swap(const PointerTo<E>&, const PointerTo<A>&);60};61 62struct F {63 friend void iter_swap(const PointerTo<F>&, const PointerTo<F>&) = delete;64};65 66// Valid except ranges::iter_swap(i1, i1).67struct G {68 friend void iter_swap(const PointerTo<G>&, const PointerTo<G>&);69 friend void iter_swap(const PointerTo<F>&, const PointerTo<G>&);70 friend void iter_swap(const PointerTo<G>&, const PointerTo<F>&);71};72 73 74static_assert( std::indirectly_swappable<PointerTo<A>, PointerTo<B>>);75static_assert(!std::indirectly_swappable<PointerTo<A>, PointerTo<C>>);76static_assert(!std::indirectly_swappable<PointerTo<A>, PointerTo<D>>);77static_assert(!std::indirectly_swappable<PointerTo<A>, PointerTo<E>>);78static_assert(!std::indirectly_swappable<PointerTo<A>, PointerTo<G>>);79