libcxx/test/std/utilities/memory/allocator.traits/rebind_traits.pass.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-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 // <memory>
  10
  11 // template <class Alloc>
  12 // struct allocator_traits
  13 // {
  14 //     template <class T> using rebind_traits = allocator_traits<rebind_alloc<T>>;
  15 //     ...
  16 // };
  17
  18 #include <memory>
  19 #include <type_traits>
  20
  21 #include "test_macros.h"
  22
  23 template <class T>
  24 struct ReboundA {};
  25
  26 template <class T>
  27 struct A
  28 {
  29     typedef T value_type;
  30
  31     template <class U> struct rebind {typedef ReboundA<U> other;};
  32 };
  33
  34 template <class T, class U>
  35 struct ReboundB {};
  36
  37 template <class T, class U>
  38 struct B
  39 {
  40     typedef T value_type;
  41
  42     template <class V> struct rebind {typedef ReboundB<V, U> other;};
  43 };
  44
  45 template <class T>
  46 struct C
  47 {
  48     typedef T value_type;
  49 };
  50
  51 template <class T, class U>
  52 struct D
  53 {
  54     typedef T value_type;
  55 };
  56
  57 template <class T>
  58 struct E
  59 {
  60     typedef T value_type;
  61
  62     template <class U> struct rebind {typedef ReboundA<U> otter;};
  63 };
  64
  65 int main(int, char**)
  66 {
  67 #if TEST_STD_VER >= 11
  68     static_assert((std::is_same<std::allocator_traits<A<char> >::rebind_traits<double>, std::allocator_traits<ReboundA<double> > >::value), "");
  69     static_assert((std::is_same<std::allocator_traits<B<int, char> >::rebind_traits<double>, std::allocator_traits<ReboundB<double, char> > >::value), "");
  70     static_assert((std::is_same<std::allocator_traits<C<char> >::rebind_traits<double>, std::allocator_traits<C<double> > >::value), "");
  71     static_assert((std::is_same<std::allocator_traits<D<int, char> >::rebind_traits<double>, std::allocator_traits<D<double, char> > >::value), "");
  72     static_assert((std::is_same<std::allocator_traits<E<char> >::rebind_traits<double>, std::allocator_traits<E<double> > >::value), "");
  73 #else
  74     static_assert((std::is_same<std::allocator_traits<A<char> >::rebind_traits<double>::other, std::allocator_traits<ReboundA<double> > >::value), "");
  75     static_assert((std::is_same<std::allocator_traits<B<int, char> >::rebind_traits<double>::other, std::allocator_traits<ReboundB<double, char> > >::value), "");
  76     static_assert((std::is_same<std::allocator_traits<C<char> >::rebind_traits<double>::other, std::allocator_traits<C<double> > >::value), "");
  77     static_assert((std::is_same<std::allocator_traits<D<int, char> >::rebind_traits<double>::other, std::allocator_traits<D<double, char> > >::value), "");
  78     static_assert((std::is_same<std::allocator_traits<E<char> >::rebind_traits<double>::other, std::allocator_traits<E<double> > >::value), "");
  79 #endif
  80
  81   return 0;
  82 }