cx_type_id.h

#pragma once

#include "cx_murmur3.h"

//----------------------------------------------------------------------------
// constexpr typeid

namespace cx
{
  namespace err
  {
    namespace
    {
      extern const char* typeid_runtime_error;
    }
  }

  template <typename T>
  struct typeid_t
  {
    template <typename>
    friend constexpr uint32_t type_id();

  private:
    constexpr static const char* name()
    {
#ifdef _MSC_VER
      // this is untested: __FUNCDNAME__ or __FUNCSIG__ ?
      return __FUNCDNAME__;
#else
      return __PRETTY_FUNCTION__;
#endif
    }
    constexpr static uint32_t id = murmur3_32(name(), 0);
  };

  template <typename T>
  constexpr uint32_t type_id()
  {
    return true ? typeid_t<T>::id :
      throw err::typeid_runtime_error;
  }
}