constexpr inline auto call_if()

in fatal/type/call_traits.h [709:723]

• 15 lines of code
• 2 McCabe index (conditional complexity)

constexpr inline auto call_if(UArgs &&...args)
  -> decltype(
    detail::call_traits_impl::call_if<
      apply_args<Predicate, Args..., UArgs...>::value
    >::template call<CallTraits, Fallback, Args...>(
      std::forward<UArgs>(args)...
    )
  )
{
  return detail::call_traits_impl::call_if<
    apply_args<Predicate, Args..., UArgs...>::value
  >::template call<CallTraits, Fallback, Args...>(
    std::forward<UArgs>(args)...
  );
}