example | ||
include | ||
test | ||
test_package | ||
.appveyor.yml | ||
.gitignore | ||
.travis.yml | ||
CMakeLists.txt | ||
conanfile.py | ||
LICENSE | ||
README.md |
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| . ` |/ _` | '_ ` _ \ / _ \/ _ \| _| | | |_ _|_ _|
| |\ | (_| | | | | | | __/ (_) | | | |____|_| |_|
|_| \_|\__,_|_| |_| |_|\___|\___/|_| \_____|
Nameof C++
Header-only C++17 library provides nameof macros and functions to simply obtain the name of a variable, type, function, macro, and enum.
Features
- C++17
- Header-only
- Dependency-free
- Compile-time
- Name of variable, member variable
- Name of type, variable type
- Name of function, member function
- Name of enum, enum variable
- Name of macro
- Enum to string
Examples
-
Nameof
// Name of variable. NAMEOF(somevar) -> "somevar" // Name of member variable. NAMEOF(person.address.zip_code) -> "zip_code" // Name of function. NAMEOF(foo<int, float>()) -> "foo" // Name of member function. NAMEOF(somevar.some_method()) -> "some_method" NAMEOF(somevar.some_method<int>()) -> "some_method" // Name of macro. NAMEOF(__LINE__) -> "__LINE__" NAMEOF(NAMEOF(structvar)) -> "NAMEOF"
-
Nameof enum
auto color = Color::RED; // Name of enum variable. NAMEOF_ENUM(color) -> "RED" nameof::nameof_enum(color) -> "RED" // Static storage enum variable to string. // This version is much lighter on the compile times and is not restricted to the enum_range limitation. NAMEOF_CONST_ENUM(Color::GREEN) -> "GREEN" nameof::nameof_enum<Color::GREEN>() -> "GREEN"
-
Nameof type
using T = const int&; T var = 42; // Name of variable type. NAMEOF_TYPE_EXPR(var) -> "int" NAMEOF_FULL_TYPE_EXPR(var) -> "const int&" nameof::nameof_type<decltype(var)>() -> "int" nameof::nameof_full_type<decltype(var)>() -> "const int&" // Name of type. NAMEOF_TYPE(T) -> "int" NAMEOF_FULL_TYPE(T) -> "const int&" nameof::nameof_type<T>() -> "int" nameof::nameof_full_type<T>() -> "const int&"
-
Compile-time
constexpr auto somevar_name = NAMEOF(somevar); // somevar_name -> "somevar" constexpr auto color_name = NAMEOF_ENUM(Color::BLUE); // or nameof::nameof_enum(Color::BLUE) // color_name -> "BLUE" constexpr auto var_type_name = NAMEOF_TYPE_EXPR(var); // or nameof::nameof_type<decltype(var)>() // var_type_name -> "int" constexpr auto type_name = NAMEOF_TYPE(T); // or nameof::nameof_type<T>() // type_name -> "int"
Remarks
-
Nameof returns
std::string_view
. If argument does not have name, returns empty string. -
Nameof expression argument are identified, but are not evaluated.
-
Nameof type returns compiler-specific type name. In all cases, reference and cv-qualifiers are ignored by
nameof_type
(that is,nameof_type<const T&>() == nameof_type<T>()
). If you need detailed name of full type, usenameof_full_type
. -
If you need name with template suffix, use NAMEOF_FULL.
// Full name of template function. NAMEOF_FULL(foo<int, float>()) -> "foo<int, float>" // Full name of template member function. NAMEOF_FULL(somevar.some_method<int>()) -> "some_method<int>"
-
If you need raw fully-qualified name, use NAMEOF_RAW.
NAMEOF_RAW(::somevar.somefield) -> "::somevar.somefield" NAMEOF_RAW(&some_class::some_method<int>) -> "&some_class::some_method<int>"
-
Enum value must be in range
[NAMEOF_ENUM_RANGE_MIN, NAMEOF_ENUM_RANGE_MAX]
. By defaultNAMEOF_ENUM_RANGE_MIN = -128
,NAMEOF_ENUM_RANGE_MAX = 128
.If need another range for all enum types by default, redefine the macro
NAMEOF_ENUM_RANGE_MIN
andNAMEOF_ENUM_RANGE_MAX
.#define NAMEOF_ENUM_RANGE_MIN 0 #define NAMEOF_ENUM_RANGE_MAX 256 #include <nameof.hpp>
If need another range for specific enum type, add specialization
enum_range
for necessary enum type.#include <nameof.hpp> enum number { one = 100, two = 200, three = 300 }; namespace nameof { template <> struct enum_range<number> { static constexpr int min = 100; static constexpr int max = 300; }; }
-
Nameof enum obtains the first defined value enums, and won't work if value are aliased.
enum ShapeKind { ConvexBegin = 0, Box = 0, // Won't work. Sphere = 1, ConvexEnd = 2, Donut = 2, // Won't work too. Banana = 3, COUNT = 4, }; // NAMEOF_ENUM(ShapeKind::Box) -> "ConvexBegin" // nameof::nameof_enum(ShapeKind::Box) -> "ConvexBegin"
Work around the issue:
enum ShapeKind { // Convex shapes, see ConvexBegin and ConvexEnd below. Box = 0, Sphere = 1, // Non-convex shapes. Donut = 2, Banana = 3, COUNT = Banana + 1, // Non-reflected aliases. ConvexBegin = Box, ConvexEnd = Sphere + 1, }; // NAMEOF_ENUM(ShapeKind::Box) -> "Box" // nameof::nameof_enum(ShapeKind::Box) -> "Box" // Non-reflected aliases. // NAMEOF_ENUM(ShapeKind::ConvexBegin) -> "Box" // nameof::nameof_enum(ShapeKind::ConvexBegin) -> "Box"
Integration
You should add required file nameof.hpp.
If you are using vcpkg on your project for external dependencies, then you can use the nameof package.
If you are using Conan to manage your dependencies, merely add nameof/x.y.z@neargye/stable
to your conan's requires, where x.y.z
is the release version you want to use.
Compiler compatibility
- Clang/LLVM >= 5
- Visual C++ >= 15.3 / Visual Studio >= 2017
- Xcode >= 9
- GCC >= 7 (GCC >= 9 for NAMEOF_ENUM)