// Licensed under the MIT License . // SPDX-License-Identifier: MIT // Copyright (c) 2018 - 2020 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 struct Base { virtual ~Base() = default; }; struct Derived : Base {}; struct SomeStruct { int somefield = 0; void SomeMethod1(int i) { somefield = i; } int SomeMethod2() const { return somefield; } }; void SomeMethod3() { std::cout << NAMEOF(SomeMethod3) << " no called!" << std::endl; } template std::string SomeMethod4(U value) { auto function_name = NAMEOF(SomeMethod4).str() .append("<") .append(NAMEOF_TYPE(T)) .append(", ") .append(NAMEOF_TYPE(U)) .append(">(") .append(NAMEOF_TYPE(U)) .append(" ") .append(NAMEOF(value).data()) .append(")"); return function_name; } template class SomeClass { public: void SomeMethod5() const { std::cout << nameof::nameof_type() << std::endl; } template C SomeMethod6() const { C t{}; std::cout << NAMEOF_TYPE_EXPR(t) << std::endl; return t; } }; struct Long { struct LL { int field = 0; }; LL ll; }; enum class Color { RED, GREEN, BLUE }; enum AnimalFlags { HasClaws = 1 << 0, CanFly = 1 << 1, EatsFish = 1 << 2, Endangered = 1 << 3 }; SomeStruct structvar; Long othervar; SomeStruct* ptrvar = &structvar; void name_to_chars(const char* name) { std::cout << name << std::endl; } void name_to_string(const std::string& name) { std::cout << name << std::endl; } void name_to_string_view(std::string_view name) { std::cout << name << std::endl; } int main() { // Compile-time. constexpr auto name = NAMEOF(structvar); using namespace std::literals::string_view_literals; static_assert("structvar"sv == name); name_to_chars(name.c_str()); // 'structvar' // or name_to_chars(name.data()); // Note: c_str() return name as null-terminated C string, no memory allocation. name_to_string(name.str()); // 'structvar' // Note: str() occure memory allocation to copy name to std::string. // or name_to_string(std::string{name}); // or name_to_string(static_cast(name)); // Note: cast to std::string occure memory allocation to copy name to std::string. name_to_string_view(name); // 'structvar' // Note: Implicit cast to std::string_view, no memory allocation. #if defined(NAMEOF_ENUM_SUPPORTED) // Nameof enum variable. auto color = Color::RED; std::cout << nameof::nameof_enum(color) << std::endl; // 'RED' std::cout << NAMEOF_ENUM(color) << std::endl; // 'RED' std::cout << nameof::nameof_enum() << std::endl; // 'GREEN' // Nameof enum flags. auto flag = static_cast(AnimalFlags::CanFly | AnimalFlags::EatsFish); std::cout << nameof::nameof_enum_flag(flag) << std::endl; // 'CanFly|EatsFish' std::cout << NAMEOF_ENUM_FLAG(flag) << std::endl; // 'CanFly|EatsFish' #endif // Nameof. std::cout << NAMEOF(structvar) << std::endl; // 'structvar' std::cout << NAMEOF(::structvar) << std::endl; // 'structvar' 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' std::cout << NAMEOF(ptrvar) << std::endl; // 'ptrvar // Nameof function. std::cout << NAMEOF(&SomeStruct::SomeMethod1) << std::endl; // 'SomeMethod1' std::cout << NAMEOF(structvar.SomeMethod2()) << std::endl; // 'SomeMethod2' std::cout << NAMEOF(SomeMethod3) << std::endl; // 'SomeMethod3' std::cout << NAMEOF(SomeMethod4(1.0f)) << std::endl; // 'SomeMethod4' std::cout << NAMEOF(&SomeClass::SomeMethod5) << std::endl; // 'SomeMethod5' std::cout << NAMEOF(&SomeClass::SomeMethod6) << std::endl; // 'SomeMethod6' // Nameof with template suffix. std::cout << NAMEOF_FULL(SomeMethod4) << std::endl; // 'SomeMethod4' std::cout << NAMEOF_FULL(&SomeClass::SomeMethod6) << std::endl; // 'SomeMethod6' // Nameof type. std::cout << nameof::nameof_type() << std::endl; // 'Long::LL' std::cout << NAMEOF_TYPE(const Long::LL&) << std::endl; // 'Long::LL' std::cout << nameof::nameof_full_type() << std::endl; // 'const Long::LL &' std::cout << NAMEOF_FULL_TYPE(const Long::LL&) << std::endl; // 'const Long::LL &' std::cout << NAMEOF_SHORT_TYPE(const Long::LL&) << std::endl; // 'LL' std::cout << NAMEOF_SHORT_TYPE(const SomeClass&) << std::endl; // 'SomeClass' // Nameof variable type. std::cout << nameof::nameof_type() << std::endl; // 'SomeStruct' std::cout << NAMEOF_TYPE_EXPR(structvar) << std::endl; // 'SomeStruct' std::cout << NAMEOF_TYPE_EXPR(std::declval>()) << std::endl; // 'SomeClass' std::cout << NAMEOF_FULL_TYPE_EXPR(std::declval>()) << std::endl; // 'const SomeClass &&' std::cout << NAMEOF_SHORT_TYPE_EXPR(std::declval>()) << std::endl; // 'SomeClass' // Nameof macro. std::cout << NAMEOF(__LINE__) << std::endl; // '__LINE__' // Nameof raw. std::cout << NAMEOF_RAW(structvar.somefield) << std::endl; // 'structvar.somefield' std::cout << NAMEOF_RAW(&SomeStruct::SomeMethod1) << std::endl; // '&SomeStruct::SomeMethod1' #if defined(NAMEOF_TYPE_RTTI_SUPPORTED) // Nameof type using RTTI. Base* ptr = new Derived(); std::cout << NAMEOF_TYPE_RTTI(ptr) << std::endl; // "Base *" std::cout << NAMEOF_TYPE_RTTI(*ptr) << std::endl; // "Derived" #endif // Some more complex example. std::cout << SomeMethod4(structvar) << std::endl; // 'SomeMethod4(SomeStruct value)' auto div = [](int x, int y) -> int { if (y == 0) { throw std::invalid_argument(NAMEOF(y).str() + " should not be zero!"); } return x / y; }; try { auto 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 name. std::cout << NAMEOF(ptrvar[0]) << std::endl; // '' std::cout << NAMEOF(42.0) << std::endl; // '' std::cout << NAMEOF(42) << std::endl; // '' std::cout << NAMEOF(42.0_deg) << std::endl; // '' std::cout << NAMEOF((structvar)) << std::endl; // '' std::cout << NAMEOF((SomeMethod4)(1.0f)) << std::endl; // '' std::cout << NAMEOF(42, 42, 42) << std::endl; // '' std::cout << NAMEOF(42 + 42) << std::endl; // '' std::cout << NAMEOF("Bad case"_string) << std::endl; // '' std::cout << NAMEOF("Bad case") << std::endl; // '' std::cout << NAMEOF("somevar.somefield") << std::endl; // '' std::cout << NAMEOF(42.f) << std::endl; // '' std::cout << NAMEOF(structvar.somefield++) << std::endl; // '' std::cout << NAMEOF(std::string{"test"}) << std::endl; // '' #endif return 0; }