3.5 KiB
3.5 KiB
Nameof C++
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Branch | Linux/OSX | Windows | License | Codacy |
---|---|---|---|---|
master |
C++ alternative to nameof operator in C#.
Used to obtain the simple name of a variable, type, member, function, macros. Before, you had to use string literals to refer to definitions, which is brittle when renaming code elements because tools do not know to check these string literals.
A nameof macros expression has this form:
std::cout << NAMEOF(person.address.zip_code) << std::endl; // prints "zip_code"
Features
- Simple name
- C++11
- Header-only
- Dependency-free
- Compile-time
- Compilation check
Examples
- Name of a variable, member or function and etc
NAMEOF(somevar) -> "somevar"
NAMEOF(somevar.somefield) -> "somefield"
NAMEOF(SomeMethod) -> "SomeMethod"
- Name of enum
NAMEOF(SomeEnum::RED) -> "RED"
NAMEOF(SomeEnum::GREEN) -> "GREEN"
- Name of type
NAMEOF(volatile const int) -> "volatile const int int"
NAMEOF(std::string) -> "string"
- Name of macros
NAMEOF(__LINE__) -> "__LINE__"
NAMEOF(__FILE__) -> "__FILE__"
- Constexpr
constexpr auto constexpr_work_fine = NAMEOF(somevar); -> "somevar"
- Compilation check
NAMEOF(std::stringgg) -> error namespace "std" has no member "stringgg"
- Validate parameters
void f(char* s) {
if (s == nullptr)
throw std::invalid_argument(NAMEOF(s));
}
- Serialization, for example json:
void to_json(json& j, const person& p) {
j = json{{NAMEOF(p.name), p.name},
{NAMEOF(p.address), p.address},
{NAMEOF(p.age), p.age}};
}
void from_json(const json& j, person& p) {
p.name = j.at(NAMEOF(p.name));
p.address = j.at(NAMEOF(p.address));
p.age = j.at(NAMEOF(p.age));
}
- Logging
void f() {
Log(NAMEOF(f), " method entry");
}
Remarks
-
The argument expression identifies a code definition, but it is never evaluated.
-
If you need fully-qualified name, use NAMEOF_FULL().
NAMEOF_FULL(somevar.somefield) -> "somevar.somefield"
NAMEOF_FULL(&SomeStruct::SomeMethod) -> "&SomeStruct::SomeMethod"
NAMEOF_FULL(std::string) -> "std::string"
- Spaces and Tabs ignored
NAMEOF( std::string ) -> "string"
NAMEOF( std::string ) -> "string"
Integration
You should add required file nameof.hpp and switch to C++11.
Compiler compatibility
- GCC
- Clang
- MSVC