StaticTypeInfo

A simple C++17 compile-time type info library.

API

The header-only library exposes two main constexpr functions: constexpr TypeName getTypeName<T>() and constexpr TypeIndex getTypeIndex<T>(). The TypeIndex may be used as a key in any hash-based container.

#include <static_type_info.h>

void example() {
  using namespace static_type_info;

  // compile-time type names
  constexpr auto name = getTypeName<int>();
  static_assert(name == "int");

  // compile-time type indices
  constexpr auto intIdx = getTypeIndex<int>();
  constexpr auto floatIdx = getTypeIndex<float>();
  static_assert(intIdx != floatIdx);

  // combine both in a single type
  constexpr auto typeID = getTypeID<int>();
  static_assert(typeID.name == "int");
  static_assert(typeID.index == getTypeIndex<int>());
}

Compatibility

The library has been tested with AppleClang 11, Visual Studio 16 2019, and gcc-9. Note that type names and indices are not compatible between compilers.

How it works

The type name is extracted from the macro __PRETTY_FUNCTION__ (clang/gcc) or __FUNCSIG__ (on MSVC) inside a probe function and converted to a string_view using the constexpr constructor. The type index is determined from the pointer to a static member of a templated string (clang / msvc) or from a 64 bit fnv1a hash of the type name (gcc and others).

How to integrate

Use CPM.cmake to easily add the headers to your CMake project.

CPMAddPackage(
  NAME StaticTypeInfo
  VERSION 1.3
  GIT_REPOSITORY https://github.com/TheLartians/StaticTypeInfo
)

target_link_libraries(myProject StaticTypeInfo)

Licence

The library is released under the MIT license. See the LICENSE for more info.