From db0b726c051f2d631b85793038677caf467a7cfe Mon Sep 17 00:00:00 2001
From: LEE KYOUNGHEON <stripe2933@gmail.com>
Date: Tue, 28 May 2024 06:17:33 +0900
Subject: [PATCH] Add MAGIC_ENUM_USE_STD_MODULE option to use standard library
 module. (#350)

---
 include/magic_enum/magic_enum.hpp             |  4 ++++
 include/magic_enum/magic_enum_containers.hpp  |  4 ++++
 include/magic_enum/magic_enum_format.hpp      |  2 ++
 include/magic_enum/magic_enum_iostream.hpp    |  2 ++
 .../magic_enum => module}/magic_enum.cppm     | 20 +++++++++++++++++++
 5 files changed, 32 insertions(+)
 rename {include/magic_enum => module}/magic_enum.cppm (80%)

diff --git a/include/magic_enum/magic_enum.hpp b/include/magic_enum/magic_enum.hpp
index 7adf87715..56b723ac0 100644
--- a/include/magic_enum/magic_enum.hpp
+++ b/include/magic_enum/magic_enum.hpp
@@ -36,6 +36,7 @@
 #define MAGIC_ENUM_VERSION_MINOR 9
 #define MAGIC_ENUM_VERSION_PATCH 5
 
+#ifndef MAGIC_ENUM_USE_STD_MODULE
 #include <array>
 #include <cstddef>
 #include <cstdint>
@@ -43,11 +44,13 @@
 #include <limits>
 #include <type_traits>
 #include <utility>
+#endif
 
 #if defined(MAGIC_ENUM_CONFIG_FILE)
 #  include MAGIC_ENUM_CONFIG_FILE
 #endif
 
+#ifndef MAGIC_ENUM_USE_STD_MODULE
 #if !defined(MAGIC_ENUM_USING_ALIAS_OPTIONAL)
 #  include <optional>
 #endif
@@ -57,6 +60,7 @@
 #if !defined(MAGIC_ENUM_USING_ALIAS_STRING_VIEW)
 #  include <string_view>
 #endif
+#endif
 
 #if defined(MAGIC_ENUM_NO_ASSERT)
 #  define MAGIC_ENUM_ASSERT(...) static_cast<void>(0)
diff --git a/include/magic_enum/magic_enum_containers.hpp b/include/magic_enum/magic_enum_containers.hpp
index 6ccd82a6a..f0022bce2 100644
--- a/include/magic_enum/magic_enum_containers.hpp
+++ b/include/magic_enum/magic_enum_containers.hpp
@@ -36,10 +36,14 @@
 #include "magic_enum.hpp"
 
 #if !defined(MAGIC_ENUM_NO_EXCEPTION) && (defined(__cpp_exceptions) || defined(__EXCEPTIONS) || defined(_CPPUNWIND))
+#ifndef MAGIC_ENUM_USE_STD_MODULE
 #  include <stdexcept>
+#endif
 #  define MAGIC_ENUM_THROW(...) throw (__VA_ARGS__)
 #else
+#ifndef MAGIC_ENUM_USE_STD_MODULE
 #  include <cstdlib>
+#endif
 #  define MAGIC_ENUM_THROW(...) std::abort()
 #endif
 
diff --git a/include/magic_enum/magic_enum_format.hpp b/include/magic_enum/magic_enum_format.hpp
index 934462e3e..e1d6f4573 100644
--- a/include/magic_enum/magic_enum_format.hpp
+++ b/include/magic_enum/magic_enum_format.hpp
@@ -50,7 +50,9 @@ namespace magic_enum::customize {
 
 #if defined(__cpp_lib_format)
 
+#ifndef MAGIC_ENUM_USE_STD_MODULE
 #include <format>
+#endif
 
 template <typename E>
 struct std::formatter<E, std::enable_if_t<std::is_enum_v<std::decay_t<E>> && magic_enum::customize::enum_format_enabled<E>(), char>> : std::formatter<std::string_view, char> {
diff --git a/include/magic_enum/magic_enum_iostream.hpp b/include/magic_enum/magic_enum_iostream.hpp
index 424e30831..eb618d757 100644
--- a/include/magic_enum/magic_enum_iostream.hpp
+++ b/include/magic_enum/magic_enum_iostream.hpp
@@ -35,7 +35,9 @@
 #include "magic_enum.hpp"
 #include "magic_enum_flags.hpp"
 
+#ifndef MAGIC_ENUM_USE_STD_MODULE
 #include <iosfwd>
+#endif
 
 namespace magic_enum {
 
diff --git a/include/magic_enum/magic_enum.cppm b/module/magic_enum.cppm
similarity index 80%
rename from include/magic_enum/magic_enum.cppm
rename to module/magic_enum.cppm
index 74f94d7fb..db43bcbaf 100644
--- a/include/magic_enum/magic_enum.cppm
+++ b/module/magic_enum.cppm
@@ -1,9 +1,23 @@
 module;
 
+#include <version>
+#ifndef MAGIC_ENUM_USE_STD_MODULE
 #include <magic_enum_all.hpp>
+#endif
 
 export module magic_enum;
 
+#ifdef MAGIC_ENUM_USE_STD_MODULE
+import std;
+
+extern "C++" {
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Winclude-angled-in-module-purview"
+#include <magic_enum_all.hpp>
+#pragma clang diagnostic pop
+}
+#endif
+
 export namespace magic_enum {
 namespace customize {
     using customize::enum_range;
@@ -54,3 +68,9 @@ namespace containers {
     using magic_enum::underlying_type;
     using magic_enum::underlying_type_t;
 }
+
+#if defined(__cpp_lib_format)
+export namespace std {
+    using std::formatter;
+}
+#endif