nameof_module/README.md
2018-03-27 13:37:17 +05:00

2 KiB

nameof() c++11

C++ alternative to nameof operator.

Used to obtain the simple name of a variable, type, function. 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 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

Example & Key Use Cases

  • Name of a variable, function and etc
NAMEOF(someVar) -> "someVar"
NAMEOF(someVar.SomeField) -> "SomeField"

NAMEOF(someVar.SomeMethod1()) -> "SomeMethod1()"
NAMEOF(&SomeStruct::SomeMethod2) -> "SomeMethod2"

NAMEOF_FUNCTION(someVar.SomeMethod1()) -> "SomeMethod1()"
NAMEOF_FUNCTION(&SomeStruct::SomeMethod2) -> "SomeMethod2"

NAMEOF_VAR(someVar) -> "someVar"
NAMEOF_VAR(someVar.SomeField) -> "SomeField"
  • Name of type
NAMEOF_TYPE(int[]) -> "int[]"
NAMEOF_TYPE(std::string) -> "string"
NAMEOF_TYPE(std::stringgg) -> error namespace "std" has no member "stringgg"
  • Constexpr
void f() {
  int i;
  constexpr auto constexpr_work_fine = NAMEOF(i); -> "i"
}
  • Compilation check
void f() {
  int i;
  NAMEOF(i); -> "i"
  NAMEOF(iii); -> error identifier "iii" is undefined
  NAMEOF_TYPE(std::stringgg) -> error namespace "std" has no member "stringgg"
}
  • Validate parameters
void f(char* s) {
  if (s == nullptr)
    throw std::invalid_argument(NAMEOF(s));
}
  • Logging
void f() {
  Log(NAMEOF(f), " method entry");
}

Remarks

If you need to get the fully-qualified name, you can use the NAMEOF_FULL(). For example:

NAMEOF_FULL(someVar.SomeField) -> "someVar.SomeField"
NAMEOF_FULL(&SomeStruct::SomeMethod2) -> "&SomeStruct::SomeMethod2"
NAMEOF_TYPE_FULL(std::string) -> "std::string"

License MIT