update doc and example

doc/limitations.md

@@ -16,6 +16,10 @@
   };
   ```
 
+  * `MAGIC_ENUM_RANGE_MAX/MAGIC_ENUM_RANGE_MIN` does not affect the maximum amount of flags.
+
+  * If enum is declared as flags, then it will not reflect the value of zero and is logically AND.
+
 * Enum value must be in range `[MAGIC_ENUM_RANGE_MIN, MAGIC_ENUM_RANGE_MAX]`.
 
   * By default `MAGIC_ENUM_RANGE_MIN = -128`, `MAGIC_ENUM_RANGE_MAX = 128`.

doc/reference.md

@@ -431,6 +431,19 @@ constexpr bool enum_flags_contains(string_view value, BinaryPredicate p) noexcep
 
 * You should add the required file `<magic_enum_flags.hpp>`.
 
+* For enum-flags add `is_flags` to specialization `enum_range` for necessary enum type. Specialization of `enum_range` must be injected in `namespace magic_enum::customize`.
+  ```cpp
+  enum class Directions { Up = 1 << 1, Down = 1 << 2, Right = 1 << 3, Left = 1 << 4 };
+  template <>
+  struct magic_enum::customize::enum_range<Directions> {
+    static constexpr bool is_flags = true;
+  };
+  ```
+
+  * `MAGIC_ENUM_RANGE_MAX/MAGIC_ENUM_RANGE_MIN` does not affect the maximum amount of flags.
+
+  * If enum is declared as flags, then it will not reflect the value of zero and is logically AND.
+
 * Examples
 
   ```cpp
@@ -439,15 +452,18 @@ constexpr bool enum_flags_contains(string_view value, BinaryPredicate p) noexcep
     Down = 2,
     Up = 4,
     Right = 8,
+    LeftAndDown = 3
   };
   template <>
   struct magic_enum::customize::enum_range<Directions> {
     static constexpr bool is_flags = true;
   };
 
-  magic_enum::enum_flags_name(Directions::Up | Directions::Right); // directions_name -> "Directions::Up|Directions::Right"
+  magic_enum::enum_flags_name(Directions::Up | Directions::Right); // -> "Directions::Up|Directions::Right"
+  magic_enum::enum_flags_name(Directions::LeftAndDown); // -> "Directions::Left|Directions::Down"
 
   magic_enum::enum_flags_contains(Directions::Up | Directions::Right); // -> true
+  magic_enum::enum_flags_contains(Directions::LeftAndDown); // -> false
 
   magic_enum::enum_flags_cast(3); // -> "Directions::Left|Directions::Down"
 
@@ -549,7 +565,7 @@ basic_ostream<Char, Traits>& operator<<(basic_ostream<Char, Traits>& os, optiona
 * Examples
 
   ```cpp
-  using namespace magic_enum::ostream_operators; // out-of-the-box ostream operators for enums.
+  using magic_enum::iostream_operators::operator<<; // out-of-the-box ostream operators for enums.
   Color color = Color::BLUE;
   std::cout << color << std::endl; // "BLUE"
   ```
@@ -568,7 +584,7 @@ basic_istream<Char, Traits>& operator>>(basic_istream<Char, Traits>& is, E& valu
 * Examples
 
   ```cpp
-  using namespace magic_enum::istream_operators; // out-of-the-box istream operators for enums.
+  using magic_enum::iostream_operators::operator>>; // out-of-the-box istream operators for enums.
   Color color;
   std::cin >> color;
   ```

example/enum_flag_example.cpp

@@ -64,7 +64,7 @@ int main() {
   auto f4_integer = magic_enum::enum_integer(AnimalFlags::HasClaws);
   std::cout << "HasClaws = " << f4_integer << std::endl; // HasClaws = 1024
 
-  using namespace magic_enum::ostream_operators; // out-of-the-box ostream operator for enum-flags.
+  using magic_enum::iostream_operators::operator<<; // out-of-the-box ostream operator for enum-flags.
   // Ostream operator for enum-flags.
   std::cout << f1 << " " << f2 << " " << f3 << std::endl; // Endangered CanFly|EatsFish HasClaws|EatsFish
 

example/example.cpp

@@ -70,7 +70,7 @@ int main() {
   auto c4_integer = magic_enum::enum_integer(Color::RED);
   std::cout << "RED = " << c4_integer << std::endl; // RED = -10
 
-  using namespace magic_enum::ostream_operators; // out-of-the-box ostream operator for all enums.
+  using magic_enum::iostream_operators::operator<<; // out-of-the-box ostream operator for all enums.
   // Ostream operator for enum.
   std::cout << "Color: " << c1 << " " << c2 << " " << c3 << std::endl; // Color: RED BLUE GREEN
 

include/magic_enum/magic_enum_iostream.hpp

@@ -105,8 +105,8 @@ std::basic_istream<Char, Traits>& operator>>(std::basic_istream<Char, Traits>& i
 
 namespace iostream_operators {
 
-using namespace ostream_operators;
-using namespace istream_operators;
+using magic_enum::ostream_operators::operator<<;
+using magic_enum::istream_operators::operator>>;
 
 } // namespace magic_enum::iostream_operators