From f4738bef44782f161e949a831cb18910a9b2a5ba Mon Sep 17 00:00:00 2001
From: neargye <neargye@gmail.com>
Date: Fri, 26 Nov 2021 11:11:51 +0200
Subject: [PATCH] fix hard-limit on enum range

---
 include/magic_enum.hpp | 11 ++---------
 1 file changed, 2 insertions(+), 9 deletions(-)

diff --git a/include/magic_enum.hpp b/include/magic_enum.hpp
index f122000..5cc6617 100644
--- a/include/magic_enum.hpp
+++ b/include/magic_enum.hpp
@@ -131,13 +131,8 @@ struct enum_range {
   static_assert(max > min, "magic_enum::customize::enum_range requires max > min.");
 };
 
-static_assert(MAGIC_ENUM_RANGE_MIN <= 0, "MAGIC_ENUM_RANGE_MIN must be less or equals than 0.");
-static_assert(MAGIC_ENUM_RANGE_MIN > (std::numeric_limits<std::int16_t>::min)(), "MAGIC_ENUM_RANGE_MIN must be greater than INT16_MIN.");
-
-static_assert(MAGIC_ENUM_RANGE_MAX > 0, "MAGIC_ENUM_RANGE_MAX must be greater than 0.");
-static_assert(MAGIC_ENUM_RANGE_MAX < (std::numeric_limits<std::int16_t>::max)(), "MAGIC_ENUM_RANGE_MAX must be less than INT16_MAX.");
-
 static_assert(MAGIC_ENUM_RANGE_MAX > MAGIC_ENUM_RANGE_MIN, "MAGIC_ENUM_RANGE_MAX must be greater than MAGIC_ENUM_RANGE_MIN.");
+static_assert((MAGIC_ENUM_RANGE_MAX - MAGIC_ENUM_RANGE_MIN) < (std::numeric_limits<std::uint16_t>::max)(), "MAGIC_ENUM_RANGE must be less than UINT16_MAX.");
 
 // If need custom names for enum, add specialization enum_name for necessary enum type.
 template <typename E>
@@ -392,7 +387,6 @@ constexpr int reflected_min() noexcept {
     return 0;
   } else {
     constexpr auto lhs = customize::enum_range<E>::min;
-    static_assert(lhs > (std::numeric_limits<std::int16_t>::min)(), "magic_enum::enum_range requires min must be greater than INT16_MIN.");
     constexpr auto rhs = (std::numeric_limits<U>::min)();
 
     if constexpr (cmp_less(rhs, lhs)) {
@@ -412,7 +406,6 @@ constexpr int reflected_max() noexcept {
     return std::numeric_limits<U>::digits - 1;
   } else {
     constexpr auto lhs = customize::enum_range<E>::max;
-    static_assert(lhs < (std::numeric_limits<std::int16_t>::max)(), "magic_enum::enum_range requires max must be less than INT16_MAX.");
     constexpr auto rhs = (std::numeric_limits<U>::max)();
 
     if constexpr (cmp_less(lhs, rhs)) {
@@ -494,7 +487,7 @@ constexpr std::size_t range_size() noexcept {
   static_assert(is_enum_v<E>, "magic_enum::detail::range_size requires enum type.");
   constexpr auto max = IsFlags ? log2(max_v<E, IsFlags>) : max_v<E, IsFlags>;
   constexpr auto min = IsFlags ? log2(min_v<E, IsFlags>) : min_v<E, IsFlags>;
-  constexpr auto range_size = max - min + U{1};
+  constexpr auto range_size = max - min + 1;
   static_assert(range_size > 0, "magic_enum::enum_range requires valid size.");
   static_assert(range_size < (std::numeric_limits<std::uint16_t>::max)(), "magic_enum::enum_range requires valid size.");