_2d_trait_self.cpp

Shows self a referntial trait

#include <bit_factory/anyxx.hpp>
#include <catch2/catch_test_macros.hpp>
#include <string>
 
namespace example_2d {
 
TRAIT_TEMPLATE_(((Base)), has_equal, Base, (),
                (ANY_FN_DEF(public, bool, is_equal, (anyxx::self const&), const,
                            [&x](T const& y) { return x == y; })))
 
template <typename Proxy = anyxx::val, typename Base = anyxx::base_trait>
using any_has_equal = anyxx::any<Proxy, has_equal<Base>>;
 
}  // namespace example_2d
 
TEST_CASE("example 2da any_has_equal") {
  using namespace example_2d;
  using namespace anyxx;
  using namespace std::string_literals;
 
  {
    any_has_equal<> a{std::in_place, "a"s};
    any_has_equal<> b{std::in_place, "b"s};
    CHECK(a.is_equal(a));
    CHECK(!b.is_equal(a));
  }
  {
    auto a = trait_as<has_equal<base_trait>>("a"s);
    auto b = trait_as<has_equal<base_trait>>("b"s);
    CHECK(a.is_equal(a));
    CHECK(!b.is_equal(a));
  }
}
 
namespace example_2d {
 
TRAIT_(has_plus, has_equal<anyxx::base_trait>,
       (ANY_FN_DEF(public, anyxx::self, plus, (anyxx::self const&), const,
                   ([&x](T const& y) {
                     return get_proxy_value(trait_as<has_plus>(x) +
                                            trait_as<has_plus>(y));
                   })),
        ANY_OP_DEF(public, anyxx::self, +, plus_op, (anyxx::self const&), const,
                   ([&x](T const& y) { return x + y; }))))
 
template <typename Box = anyxx::val>
using any_has_plus = anyxx::any<Box, has_plus>;
 
}  // namespace example_2d
 
TEST_CASE("example 2db any_has_plus dynamic") {
  using namespace example_2d;
  using namespace anyxx;
  using namespace std::string_literals;
  {
    any_has_plus<> a{std::in_place, "a"s};
    any_has_plus<> b{std::in_place, "b"s};
    CHECK((a + a).is_equal(any_has_plus<>{"aa"s}));
    CHECK((a + b).is_equal(any_has_plus<>{"ab"s}));
    CHECK((a.plus(a)).is_equal(any_has_plus<>{"aa"s}));
    CHECK((a.plus(b)).is_equal(any_has_plus<>{"ab"s}));
  }
}
TEST_CASE("example 2db any_has_plus static") {
  using namespace example_2d;
  using namespace anyxx;
  using namespace std::string_literals;
  {
    auto a = trait_as<has_plus>("a"s);
    auto b = trait_as<has_plus>("b"s);
    auto aa = trait_as<has_plus>("aa"s);
    auto bb = trait_as<has_plus>("ab"s);
    CHECK((a + a).is_equal(aa));
    CHECK((a + b).is_equal(bb));
    CHECK((a.plus(a)).is_equal(aa));
    CHECK((a.plus(b)).is_equal(bb));
  }
}