// nameof example // // Licensed under the MIT License . // Copyright (c) 2018 Daniil Goncharov . // // 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 #include #include #include #include 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 T SomeMethod4() { return T{}; } template class SomeClass { public: void SomeMethod5() const { std::cout << NAMEOF_TYPE_T(T) << std::endl; } template 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) << std::endl; // SomeMethod4 std::cout << NAMEOF_FULL(SomeMethod4) << std::endl; // SomeMethod4 std::cout << NAMEOF(&SomeClass::SomeMethod5) << std::endl; // SomeMethod5 std::cout << NAMEOF(&SomeClass::SomeMethod6) << std::endl; // SomeMethod6 std::cout << NAMEOF_FULL(&SomeClass::SomeMethod6) << std::endl; // SomeMethod6 // Type name. std::cout << NAMEOF_TYPE(structvar) << std::endl; // SomeStruct std::cout << NAMEOF_TYPE(othervar.ll) << std::endl; // LL std::cout << NAMEOF_TYPE(SomeClass{}) << std::endl; // SomeClass std::cout << NAMEOF_TYPE(othervar.ll) << std::endl; // Long::LL std::cout << NAMEOF_TYPE(std::declval>()) << std::endl; // const SomeClass && std::cout << NAMEOF_TYPE_T(const SomeClass volatile *) << std::endl; // const volatile SomeClass * std::cout << NAMEOF_TYPE_T(SomeClass) << std::endl; // SomeClass // Raw name. std::cout << NAMEOF_RAW(volatile const int) << std::endl; // volatile const int 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 std::cout << NAMEOF_RAW(Long::LL) << std::endl; // Long::LL 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 0 // This expression does not have a name. std::cout << NAMEOF("Bad case") << std::endl; // '"Bad case"' std::cout << NAMEOF("Bad case"_string) << std::endl; // '"Bad case"_string' std::cout << NAMEOF("somevar.somefield") << std::endl; // 'somefield"' 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{"test"}' std::cout << NAMEOF(SomeMethod4()) << std::endl; // '()' std::cout << NAMEOF(std::basic_string) << std::endl; // '' std::cout << NAMEOF(ptrvar[0]) << std::endl; // 'ptrvar[0]' std::cout << NAMEOF(intvar + intvar) << std::endl; // ' intvar' std::cout << NAMEOF(NAMEOF(intvar)) << std::endl; // 'NAMEOF(intvar)' std::cout << NAMEOF(std::cout << intvar << std::endl) << std::endl; // 'endl' std::cout << NAMEOF(decltype(intvar)) << std::endl; // 'decltype(intvar)' std::cout << NAMEOF(typeid(intvar)) << std::endl; // 'typeid(intvar)' std::cout << NAMEOF((intvar)) << std::endl; // '(intvar)' #endif return 0; }