From 5518b2b1559342fadec14ad979819d15a8542d43 Mon Sep 17 00:00:00 2001
From: ToruNiina <niina.toru.68u@gmail.com>
Date: Wed, 14 Apr 2021 13:09:25 +0900
Subject: [PATCH] refactor: simplify last_one_in_pack meta func

---
 toml/utility.hpp | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/toml/utility.hpp b/toml/utility.hpp
index 96e53db..4a6b430 100644
--- a/toml/utility.hpp
+++ b/toml/utility.hpp
@@ -117,10 +117,8 @@ decltype(auto) last_one(T&& /*head*/, Ts&& ... tail) noexcept
 // line #3, so `decltype()` cannot deduce the type returned from `last_one`.
 // So we need to determine return type in a different way, like a meta func.
 
-template<typename ... Ts>
-struct last_one_in_pack;
 template<typename T, typename ... Ts>
-struct last_one_in_pack<T, Ts...>
+struct last_one_in_pack
 {
     using type = typename last_one_in_pack<Ts...>::type;
 };
@@ -137,9 +135,8 @@ T&& last_one(T&& tail) noexcept
 {
     return std::forward<T>(tail);
 }
-
 template<typename T, typename ... Ts>
-last_one_in_pack_t<Ts&& ...>
+enable_if_t<(sizeof...(Ts) > 0), last_one_in_pack_t<Ts&& ...>>
 last_one(T&& /*head*/, Ts&& ... tail)
 {
     return last_one(std::forward<Ts>(tail)...);