libcxx/test/std/utilities/optional/optional.comp_with_t/equal.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 // UNSUPPORTED: c++03, c++11, c++14
  10 // <optional>
  11
  12 // template <class T, class U> constexpr bool operator==(const optional<T>& x, const U& v);
  13 // template <class T, class U> constexpr bool operator==(const U& v, const optional<T>& x);
  14
  15 #include <optional>
  16
  17 #include "test_macros.h"
  18
  19 using std::optional;
  20
  21 struct X {
  22   int i_;
  23
  24   constexpr X(int i) : i_(i) {}
  25 };
  26
  27 constexpr bool operator==(const X& lhs, const X& rhs) {
  28   return lhs.i_ == rhs.i_;
  29 }
  30
  31 int main(int, char**) {
  32   {
  33     typedef X T;
  34     typedef optional<T> O;
  35
  36     constexpr T val(2);
  37     constexpr O o1;      // disengaged
  38     constexpr O o2{1};   // engaged
  39     constexpr O o3{val}; // engaged
  40
  41     static_assert(!(o1 == T(1)), "");
  42     static_assert((o2 == T(1)), "");
  43     static_assert(!(o3 == T(1)), "");
  44     static_assert((o3 == T(2)), "");
  45     static_assert((o3 == val), "");
  46
  47     static_assert(!(T(1) == o1), "");
  48     static_assert((T(1) == o2), "");
  49     static_assert(!(T(1) == o3), "");
  50     static_assert((T(2) == o3), "");
  51     static_assert((val == o3), "");
  52   }
  53   {
  54     using O = optional<int>;
  55     constexpr O o1(42);
  56     static_assert(o1 == 42l, "");
  57     static_assert(!(101l == o1), "");
  58   }
  59   {
  60     using O = optional<const int>;
  61     constexpr O o1(42);
  62     static_assert(o1 == 42, "");
  63     static_assert(!(101 == o1), "");
  64   }
  65
  66   return 0;
  67 }