nameof_module/example/example.cpp

// nameof example
//
// Licensed under the MIT License <http://opensource.org/licenses/MIT>.
// Copyright (c) 2018 Daniil Goncharov <neargye@gmail.com>.
//
// Permission is hereby  granted, free of charge, to any  person obtaining a copy
// of this software and associated  documentation files (the "Software"), to deal
// in the Software  without restriction, including without  limitation the rights
// to  use, copy,  modify, merge,  publish, distribute,  sublicense, and/or  sell
// copies  of  the Software,  and  to  permit persons  to  whom  the Software  is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
//
// THE SOFTWARE  IS PROVIDED "AS  IS", WITHOUT WARRANTY  OF ANY KIND,  EXPRESS OR
// IMPLIED,  INCLUDING BUT  NOT  LIMITED TO  THE  WARRANTIES OF  MERCHANTABILITY,
// FITNESS FOR  A PARTICULAR PURPOSE AND  NONINFRINGEMENT. IN NO EVENT  SHALL THE
// AUTHORS  OR COPYRIGHT  HOLDERS  BE  LIABLE FOR  ANY  CLAIM,  DAMAGES OR  OTHER
// LIABILITY, WHETHER IN AN ACTION OF  CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE  OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.

#include <nameof.hpp>

#include <iostream>
#include <string>
#include <stdexcept>
#include <typeinfo>

constexpr long double operator"" _deg(long double deg) {
  return deg * 3.141592 / 180.0;
}

std::string operator"" _string(const char* str, std::size_t) {
  return std::string{str};
}

struct SomeStruct {
  int somefield = 0;

  void SomeMethod1(const int i) { somefield = i; }

  int SomeMethod2() const { return somefield; }
};

void SomeMethod3() {
  std::cout << NAMEOF(SomeMethod3) << " no called!" << std::endl;
}

template <typename T>
std::string SomeMethod4() {
  std::cout << NAMEOF_TYPE_T(T) << std::endl;
  return NAMEOF_FULL(SomeMethod4<T>);
}

template <typename T>
class SomeClass {
public:
  void SomeMethod5() const {
    std::cout << nameof::NameofType<T>() << std::endl;
  }

  template <typename C>
  C SomeMethod6() const {
    C t{};
    std::cout << NAMEOF_TYPE(t) << std::endl;
    return t;
  }
};

struct Long {
  struct LL {
    int field = 0;
  };
  LL ll;
};

enum class Color { RED, GREEN, BLUE };

SomeStruct structvar;
Long othervar;
SomeStruct* ptrvar = &structvar;

int main() {
  // Compile-time nameof.
  constexpr auto constexpr_work_fine = NAMEOF(structvar);
  static_assert("structvar" == constexpr_work_fine, "");

  // Enum name.
  std::cout << NAMEOF(Color::RED) << std::endl; // RED

  // Variable name.
  std::cout << NAMEOF(structvar) << std::endl; // structvar
  std::cout << NAMEOF(::structvar) << std::endl; // structvar

  // Member name.
  std::cout << NAMEOF(structvar.somefield) << std::endl; // somefield
  std::cout << NAMEOF((&structvar)->somefield) << std::endl; // somefield
  std::cout << NAMEOF(othervar.ll.field) << std::endl; // field

  // Function name.
  std::cout << NAMEOF(&SomeStruct::SomeMethod1) << std::endl; // SomeMethod1
  std::cout << NAMEOF(&SomeStruct::SomeMethod2) << std::endl; // SomeMethod2
  std::cout << NAMEOF(SomeMethod3) << std::endl; // SomeMethod3

  std::cout << NAMEOF(SomeMethod4<int>()) << std::endl; // SomeMethod4
  std::cout << NAMEOF(SomeMethod4<int>) << std::endl; // SomeMethod4
  std::cout << NAMEOF_FULL(SomeMethod4<int>) << std::endl; // SomeMethod4<int>

  std::cout << NAMEOF(&SomeClass<int>::SomeMethod5) << std::endl; // SomeMethod5

  std::cout << NAMEOF(&SomeClass<int>::SomeMethod6<long int>) << std::endl; // SomeMethod6
  std::cout << NAMEOF_FULL(&SomeClass<int>::SomeMethod6<long int>) << std::endl; // SomeMethod6<long int>

  // Type name.
  std::cout << NAMEOF_TYPE(structvar) << std::endl; // SomeStruct
  std::cout << NAMEOF_TYPE(othervar.ll) << std::endl; // LL
  std::cout << NAMEOF_TYPE(SomeClass<int>{}) << std::endl; // SomeClass
  std::cout << NAMEOF_TYPE(othervar.ll) << std::endl; // Long::LL
  std::cout << NAMEOF_TYPE(std::declval<const SomeClass<int>>()) << std::endl; // const SomeClass<int> &&

  std::cout << NAMEOF_TYPE_T(const SomeClass<int> volatile *) << std::endl; // const volatile SomeClass<int> *
  std::cout << NAMEOF_TYPE_T(SomeClass<int>) << std::endl; // SomeClass<int>

  // Raw name.
  std::cout << NAMEOF_RAW(__LINE__) << std::endl; // __LINE__
  std::cout << NAMEOF_RAW(structvar.somefield) << std::endl; // structvar.somefield
  std::cout << NAMEOF_RAW(&SomeStruct::SomeMethod1) << std::endl; // &SomeStruct::SomeMethod1

  const auto div = [](int x, int y) -> int {
    if (y == 0) {
      throw std::invalid_argument(std::string(NAMEOF(y)).append(" should not be zero!"));
    }
    return x / y;
  };

  try {
    const int z = div(10, 0);
    std::cout << z << std::endl;
  } catch (const std::exception& e) {
    std::cout << e.what() << std::endl; // y should not be zero!
  }

  /* Remarks */
#if 1
  // This expression does not have a name.
  std::cout << NAMEOF("Bad case"_string) << std::endl; // '_string'
  std::cout << NAMEOF(42.0) << std::endl; // '0'
  std::cout << NAMEOF(42.f) << std::endl; // 'f'
  std::cout << NAMEOF(42) << std::endl; // '42'
  std::cout << NAMEOF(42.0_deg) << std::endl; // '0_deg'
  std::cout << NAMEOF(std::string()) << std::endl; // 'string'
  std::cout << NAMEOF(std::string{}) << std::endl; // 'string'
  std::cout << NAMEOF(std::string{"test"}) << std::endl; // 'string'
  std::cout << NAMEOF(structvar.somefield + structvar.somefield) << std::endl; // ' somefield'
  std::cout << NAMEOF(42 + 42) << std::endl; // ' 42'
  std::cout << NAMEOF(NAMEOF(structvar)) << std::endl; // 'NAMEOF'
#endif

#if 0
  // This expression does not compilation.
  std::cout << NAMEOF("Bad case") << std::endl; // ''
  std::cout << NAMEOF("somevar.somefield") << std::endl; // ''
  std::cout << NAMEOF(std::basic_string<char>) << std::endl; // ''
  std::cout << NAMEOF(ptrvar[0]) << std::endl; // 'ptrvar[0]'
  std::cout << NAMEOF(std::cout << structvar << std::endl) << std::endl; // ''
  std::cout << NAMEOF(decltype(structvar)) << std::endl; // ''
  std::cout << NAMEOF(typeid(structvar)) << std::endl; // ''
  std::cout << NAMEOF((structvar)) << std::endl; // ''
#endif

  return 0;
}