From 081a77b96ace137c7474a05d3b1ea1d97980e261 Mon Sep 17 00:00:00 2001
From: sajimon <kvz5544@gmail.com>
Date: Thu, 17 Jun 2021 15:06:27 +0200
Subject: [PATCH] Add ability to include external configuration header (#86)

* Add ability to include external configuration header

* Add documentation regarding MAGIC_ENUM_CONFIG_FILE
---
 doc/reference.md       | 16 ++++++++++++++++
 include/magic_enum.hpp |  4 ++++
 2 files changed, 20 insertions(+)

diff --git a/doc/reference.md b/doc/reference.md
index 100ba2e..6e2049b 100644
--- a/doc/reference.md
+++ b/doc/reference.md
@@ -38,6 +38,22 @@
   #define MAGIC_ENUM_USING_ALIAS_OPTIONAL template <typename T> using optional = my_lib::Optional<T>;
   #include <magic_enum.hpp>
   ```
+  Optionally define `MAGIC_ENUM_CONFIG_FILE` i.e., in your build system, with path to header file with defined 
+  macros or constants, for example:
+  
+  ```cpp
+  #define MAGIC_ENUM_CONFIG_FILE "my_magic_enum_cfg.hpp"
+  ```
+  my_magic_enum_cfg.hpp:
+  ```cpp
+  #include <my_lib/string.hpp>
+  #include <my_lib/string_view.hpp>
+  #define MAGIC_ENUM_USING_ALIAS_STRING using string = my_lib::String;
+  #define MAGIC_ENUM_USING_ALIAS_STRING_VIEW using string_view = my_lib::StringView;
+  #define MAGIC_ENUM_USING_ALIAS_OPTIONAL template <typename T> using optional = my_lib::Optional<T>;
+  #define MAGIC_ENUM_RANGE_MIN 0
+  #define MAGIC_ENUM_RANGE_MAX 255
+  ```
 
 ## `enum_cast`
 
diff --git a/include/magic_enum.hpp b/include/magic_enum.hpp
index 18c2804..0a03c4b 100644
--- a/include/magic_enum.hpp
+++ b/include/magic_enum.hpp
@@ -45,6 +45,10 @@
 #include <type_traits>
 #include <utility>
 
+#if defined(MAGIC_ENUM_CONFIG_FILE)
+#include MAGIC_ENUM_CONFIG_FILE
+#endif
+
 #if !defined(MAGIC_ENUM_USING_ALIAS_OPTIONAL)
 #include <optional>
 #endif