meta::equality_comparable

Defined in header <mgs/meta/concepts/equality_comparable.hpp>.

template <typename T>
concept equality_comparable = meta::weakly_equality_comparable_with<T, T>;

Pre-C++20 implementation of the std::equality_comparable concept.

---

Concept emulation

namespace mgs {
namespace meta {

template <typename T>
struct is_equality_comparable { /* ... */ };

template <typename T>
constexpr auto is_equality_comparable_v = is_equality_comparable<T>::value;

template <typename T,
          typename = std::enable_if_t<is_equality_comparable_v<T>>>
using equality_comparable = T;

} // namespace meta
} // namespace mgs

Example

#include <mgs/meta/concepts/equality_comparable.hpp>

using namespace mgs::meta;

static_assert(is_equality_comparable_v<std::string>, "");
static_assert(!is_equality_comparable_v<std::mutex>, "");

See also

• meta::weakly_equality_comparable_with