enum_cast
obtains enum value from string or integer.enum_value
returns enum value at specified index.enum_values
obtains enum value sequence.enum_count
returns number of enum values.enum_integer
obtains integer value from enum value.enum_name
returns name from enum value.enum_names
obtains string enum name sequence.enum_entries
obtains pair (value enum, string enum name) sequence.enum_index
obtains index in enum value sequence from enum value.enum_contains
checks whether enum contains enumerator with such value.enum_type_name
returns type name of enum.enum_fuse
returns a bijective mix of enum values.enum_switch
allows runtime enum value transformation to constexpr context.enum_for_each
calls a function with all enum constexpr value.enum_flags
API from enum-flags.is_unscoped_enum
checks whether type is an Unscoped enumeration.is_scoped_enum
checks whether type is an Scoped enumeration.underlying_type
improved UB-free "SFINAE-friendly" underlying_type.ostream_operators
ostream operators for enums.bitwise_operators
bitwise operators for enums.containers::array
array container for enums.containers::bitset
bitset container for enums.containers::set
set container for enums.
-
Before use, read the limitations of functionality.
-
To check is magic_enum supported compiler use macro
MAGIC_ENUM_SUPPORTED
or constexpr constantmagic_enum::is_magic_enum_supported
.
If magic_enum used on unsupported compiler, occurs the compilation error. To suppress error define macroMAGIC_ENUM_NO_CHECK_SUPPORT
. -
To add custom enum or type names see the example.
-
To change the type of strings or ortional, use special macros:
#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>; #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:#define MAGIC_ENUM_CONFIG_FILE "my_magic_enum_cfg.hpp"
my_magic_enum_cfg.hpp:
#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
-
To add support for non-ASCII enumeration identifier, use special macros:
#define MAGIC_ENUM_ENABLE_NONASCII #include <magic_enum.hpp>
template <typename E>
constexpr optional<E> enum_cast(underlying_type_t<E> value) noexcept;
template <typename E>
constexpr optional<E> enum_cast(string_view value) noexcept;
template <typename E, typename BinaryPredicate>
constexpr optional<E> enum_cast(string_view value, BinaryPredicate p) noexcept(is_nothrow_invocable_v<BinaryPredicate>);
-
Obtains enum value from string or integer.
-
Returns
optional<E>
, usinghas_value()
to check contains enum value andvalue()
to get the enum value. -
If argument does not enum value, returns empty
optional
. -
Examples
-
String to enum value.
string color_name{"GREEN"}; auto color = magic_enum::enum_cast<Color>(color_name); if (color.has_value()) { // color.value() -> Color::GREEN } auto color_or_default = magic_enum::enum_cast<Color>(value).value_or(Color::NONE);
-
Integer to enum value.
int color_integer = 2; auto color = magic_enum::enum_cast<Color>(color_integer); if (color.has_value()) { // color.value() -> Color::RED } auto color_or_default = magic_enum::enum_cast<Color>(value).value_or(Color::NONE);
-
template <typename E>
constexpr E enum_value(size_t index) noexcept;
template <typename E, size_t I>
constexpr E enum_value() noexcept;
-
Returns enum value at specified index.
enum_value(value)
no bounds checking is performed: the behavior is undefined ifindex >= number of enum values
.enum_value<value>()
check ifI >= number of enum values
, occurs the compilation errormagic_enum::enum_value out of range
.
-
Examples
int i = 1; Color color = magic_enum::enum_value<Color>(i); // color -> Color::BLUE
Color color = magic_enum::enum_value<Color, 1>(); // color -> Color::BLUE
template <typename E>
constexpr array<E, N> enum_values() noexcept;
-
Returns
array<E, N>
with all enum values whereN = number of enum values
, sorted by enum value. -
Examples
constexpr auto colors = magic_enum::enum_values<Color>(); // colors -> {Color::RED, Color::BLUE, Color::GREEN} // colors[0] -> Color::RED
template <typename E>
constexpr size_t enum_count() noexcept;
-
Returns number of enum values.
-
Examples
constexpr auto color_count = magic_enum::enum_count<Color>(); // color_count -> 3
template <typename E>
constexpr underlying_type_t<E> enum_integer(E value) noexcept;
template <typename E>
constexpr underlying_type_t<E> enum_underlying(E value) noexcept;
-
Returns integer value from enum value.
-
Examples
Color color = Color::RED; auto color_integer = magic_enum::enum_integer(color); // color -> 2
template <typename E>
constexpr string_view enum_name(E value) noexcept;
template <auto V>
constexpr string_view enum_name() noexcept;
-
Returns name from enum value as
string_view
with null-terminated string.- If enum value does not have name or out of range,
enum_name(value)
returns empty string. - If enum value does not have name,
enum_name<value>()
occurs the compilation errormagic_enum::enum_name enum value does not have a name
.
- If enum value does not have name or out of range,
-
enum_name<value>()
is much lighter on the compile times and is not restricted to the enum_range limitation. -
Examples
Color color = Color::RED; auto color_name = magic_enum::enum_name(color); // color_name -> "RED"
constexpr Color color = Color::BLUE; constexpr auto color_name = magic_enum::enum_name<color>(); // color_name -> "BLUE"
template <typename E>
constexpr array<string_view, N> enum_names() noexcept;
-
Returns
array<string_view, N>
with all names whereN = number of enum values
, sorted by enum value. -
Examples
constexpr auto color_names = magic_enum::enum_names<Color>(); // color_names -> {"RED", "BLUE", "GREEN"} // color_names[0] -> "RED"
template <typename E>
constexpr array<pair<E, string_view>, N> enum_entries() noexcept;
-
Returns
array<pair<E, string_view>, N>
with all pairs (value, name) whereN = number of enum values
, sorted by enum value. -
Examples
constexpr auto color_entries = magic_enum::enum_entries<Color>(); // color_entries -> {{Color::RED, "RED"}, {Color::BLUE, "BLUE"}, {Color::GREEN, "GREEN"}} // color_entries[0].first -> Color::RED // color_entries[0].second -> "RED"
template <typename E>
constexpr optional<size_t> enum_index(E value) noexcept;
template <auto V>
constexpr size_t enum_index() noexcept;
-
Obtains index in enum values from enum value.
enum_index(value)
returnsoptional<size_t>
with index.enum_index<value>()
returns index. If enum value does not have a index, occurs the compilation errormagic_enum::enum_index enum value does not have a index
.
-
Examples
constexpr auto color_index = magic_enum::enum_index(Color::BLUE); // color_index.value() -> 1 // color_index.has_value() -> true
constexpr auto color_index = magic_enum::enum_index<Color::BLUE>(); // color_index -> 1
template <typename E>
constexpr bool enum_contains(E value) noexcept;
template <typename E>
constexpr bool enum_contains(underlying_type_t<E> value) noexcept;
template <typename E>
constexpr bool enum_contains(string_view value) noexcept;
template <typename E, typename BinaryPredicate>
constexpr optional<E> enum_contains(string_view value, BinaryPredicate p) noexcept(is_nothrow_invocable_v<BinaryPredicate>);
-
Checks whether enum contains enumerator with such value.
-
Returns true is enum contains value, otherwise false.
-
Examples
magic_enum::enum_contains(Color::GREEN); // -> true magic_enum::enum_contains<Color>(2); // -> true magic_enum::enum_contains<Color>(123); // -> false magic_enum::enum_contains<Color>("GREEN"); // -> true magic_enum::enum_contains<Color>("fda"); // -> false
template <typename E>
constexpr string_view enum_type_name() noexcept;
-
Returns type name of enum as
string_view
null-terminated string. -
Examples
Color color = Color::RED; auto type_name = magic_enum::enum_type_name<decltype(color)>(); // type_name -> "Color"
template <typename... Es>
[[nodiscard]] constexpr optional<enum_fuse_t> enum_fuse(Es... values) noexcept;
-
You should add the required file
<magic_enum_fuse.hpp>
. -
Returns a typesafe bijective mix of several enum values. This can be used to emulate 2D switch/case statements.
-
Return type is
optional<enum_fuse_t>
whereenum_fuse_t
is an incomplete enum, it is unique for any given combination ofEs...
. -
Switch/case statement over an incomplete enum is a Visual Studio warning C4064
- You have to silent (/wd4064) or ignore it.
- Alternatively, define
MAGIC_ENUM_NO_TYPESAFE_ENUM_FUSE
to disable type-safety (enum_fuse_t
equalsuintmax_t
).
-
Examples
switch (magic_enum::enum_fuse(color, direction).value()) { case magic_enum::enum_fuse(Color::RED, Directions::Up).value(): // ... case magic_enum::enum_fuse(Color::BLUE, Directions::Down).value(): // ... case magic_enum::enum_fuse(Directions::BLUE, Color::Down).value(): // Compilation error // ... }
template <typename Result = void, typename E, typename Lambda>
constexpr Result enum_switch(Lambda&& lambda, E value);
template <typename Result, typename E, typename Lambda>
constexpr Result enum_switch(Lambda&& lambda, E value, Result&& result);
-
You should add the required file
<magic_enum_switch.hpp>
. -
Examples
Color color = Color::RED; magic_enum::enum_switch([] (auto val) { constexpr Color c_color = val; // ... }, color);
template <typename E, typename Lambda>
constexpr auto enum_for_each(Lambda&& lambda);
-
Examples
magic_enum::enum_for_each<Color>([] (auto val) { constexpr Color c_color = val; // ... });
template <typename E>
string enum_flags_name(E value);
template <typename E>
constexpr optional<E> enum_flags_cast(underlying_type_t<E> value) noexcept;
template <typename E>
constexpr optional<E> enum_flags_cast(string_view value) noexcept;
template <typename E, typename BinaryPredicate>
constexpr optional<E> enum_flags_cast(string_view value, BinaryPredicate p) noexcept(is_nothrow_invocable_v<BinaryPredicate>);
template <typename E>
constexpr bool enum_flags_contains(E value) noexcept;
template <typename E>
constexpr bool enum_flags_contains(underlying_type_t<E> value) noexcept;
template <typename E>
constexpr bool enum_flags_contains(string_view value) noexcept;
template <typename E, typename BinaryPredicate>
constexpr optional<E> enum_flags_contains(string_view value, BinaryPredicate p) noexcept(is_nothrow_invocable_v<BinaryPredicate>);
-
Examples
auto directions_name = magic_enum::enum_flags_name(Directions::Up | Directions::Right); // directions_name -> "Directions::Up|Directions::Right"
template <typename T>
struct is_unscoped_enum;
template <typename T>
inline constexpr bool is_unscoped_enum_v = is_unscoped_enum<T>::value;
-
Checks whether type is an Unscoped enumeration.
-
Provides the member constant value which is equal to true, if T is an Unscoped enumeration type.
Otherwise, value is equal to false. -
Examples
magic_enum::is_unscoped_enum<color>::value -> true magic_enum::is_unscoped_enum<Direction>::value -> false // Helper variable template. magic_enum::is_unscoped_enum_v<color> -> true
template <typename T>
struct is_scoped_enum;
template <typename T>
inline constexpr bool is_scoped_enum_v = is_scoped_enum<T>::value;
-
Checks whether type is an Scoped enumeration.
-
Provides the member constant value which is equal to true, if T is an Scoped enumeration type.
Otherwise, value is equal to false. -
Examples
magic_enum::is_scoped_enum<color>::value -> false magic_enum::is_scoped_enum<Direction>::value -> true // Helper variable template. magic_enum::is_scoped_enum_v<Direction> -> true
template <typename T>
struct underlying_type;
template <typename T>
using underlying_type_t = typename underlying_type<T>::type;
-
Improved UB-free "SFINAE-friendly" underlying_type.
-
If T is a complete enumeration type, provides a member typedef type that names the underlying type of T.
Otherwise, if T is not an enumeration type, there is no member type.
Otherwise (T is an incomplete enumeration type), the program is ill-formed. -
Examples
magic_enum::underlying_type<color>::type -> int // Helper types. magic_enum::underlying_type_t<Direction> -> int
template <typename Char, typename Traits, typename E>
basic_ostream<Char, Traits>& operator<<(basic_ostream<Char, Traits>& os, E value);
template <typename Char, typename Traits, typename E>
basic_ostream<Char, Traits>& operator<<(basic_ostream<Char, Traits>& os, optional<E> value);
-
Out-of-the-box ostream operators for all enums.
-
Examples
using namespace magic_enum::ostream_operators; // out-of-the-box ostream operators for enums. Color color = Color::BLUE; std::cout << color << std::endl; // "BLUE"
template <typename E>
constexpr E operator~(E rhs) noexcept;
template <typename E>
constexpr E operator|(E lhs, E rhs) noexcept;
template <typename E>
constexpr E operator&(E lhs, E rhs) noexcept;
template <typename E>
constexpr E operator^(E lhs, E rhs) noexcept;
template <typename E>
constexpr E& operator|=(E& lhs, E rhs) noexcept;
template <typename E>
constexpr E& operator&=(E& lhs, E rhs) noexcept;
template <typename E>
constexpr E& operator^=(E& lhs, E rhs) noexcept;
-
Out-of-the-box bitwise operators for all enums.
-
Examples
enum class Flags { A = 1 << 0, B = 1 << 1, C = 1 << 2, D = 1 << 3 }; using namespace magic_enum::bitwise_operators; // out-of-the-box bitwise operators for enums. // Support operators: ~, |, &, ^, |=, &=, ^=. Flags flags = Flags::A | Flags::B & ~Flags::C;
template<typename E, typename V, typename Index = default_indexing<E>>
struct array {
constexpr reference at(E pos);
constexpr const_reference at(E pos) const;
constexpr reference operator[](E pos) noexcept;
constexpr const_reference operator[](E pos) const noexcept;
constexpr reference front() noexcept;
constexpr const_reference front() const noexcept;
constexpr reference back() noexcept;
constexpr const_reference back() const noexcept;
constexpr pointer data() noexcept;
constexpr const_pointer data() const noexcept;
constexpr iterator begin() noexcept;
constexpr const_iterator begin() const noexcept;
constexpr const_iterator cbegin() const noexcept;
constexpr iterator end() noexcept;
constexpr const_iterator end() const noexcept;
constexpr const_iterator cend() const noexcept;
constexpr iterator rbegin() noexcept;
constexpr const_iterator rbegin() const noexcept;
constexpr const_iterator crbegin() const noexcept;
constexpr iterator rend() noexcept;
constexpr const_iterator rend() const noexcept;
constexpr const_iterator crend() const noexcept;
constexpr bool empty() const noexcept;
constexpr size_type size() const noexcept;
constexpr size_type max_size() const noexcept;
constexpr void fill( const V& value );
constexpr void swap(array& other) noexcept(std::is_nothrow_swappable_v<V>);
friend constexpr bool operator==(const array& a1, const array& a2);
friend constexpr bool operator!=(const array& a1, const array& a2);
friend constexpr bool operator<(const array& a1, const array& a2);
friend constexpr bool operator<=(const array& a1, const array& a2);
friend constexpr bool operator>(const array& a1, const array& a2);
friend constexpr bool operator>=(const array& a1, const array& a2);
}
-
STL like array for all enums.
-
Examples
constexpr magic_enum::containers::array<Color, RGB> color_rgb_array {{{{255, 0, 0}, {0, 255, 0}, {0, 0, 255}}}};
magic_enum::containers::array<Color, RGB> color_rgb_array {}; color_rgb_array[Color::RED] = {255, 0, 0}; color_rgb_array[Color::GREEN] = {0, 255, 0}; color_rgb_array[Color::BLUE] = {0, 0, 255}; std::get<Color::BLUE>(color_rgb_array) // -> RGB{0, 0, 255}
template<typename E, typename Index = default_indexing<E>>
class bitset {
constexpr explicit bitset(detail::raw_access_t = raw_access) noexcept;
constexpr explicit bitset(detail::raw_access_t, unsigned long long val);
constexpr explicit bitset(detail::raw_access_t,
string_view sv,
string_view::size_type pos = 0,
string_view::size_type n = string_view::npos,
char zero = '0',
char one = '1');
constexpr explicit bitset(detail::raw_access_t,
const char* str,
std::size_t n = ~std::size_t{},
char zero = '0',
char one = '1');
constexpr bitset(std::initializer_list<E> starters);
template<typename V = E>
constexpr explicit bitset(std::enable_if_t<magic_enum::detail::is_flags_v<V>, E> starter);
template<typename Cmp = std::equal_to<>>
constexpr explicit bitset(string_view sv,
Cmp&& cmp = {},
char sep = '|');
friend constexpr bool operator==( const bitset& lhs, const bitset& rhs ) noexcept;
friend constexpr bool operator!=( const bitset& lhs, const bitset& rhs ) noexcept;
constexpr bool operator[](E pos) const noexcept;
constexpr reference operator[](E pos) noexcept;
constexpr bool test(E pos) const;
constexpr bool all() const noexcept;
constexpr bool any() const noexcept;
constexpr bool none() const noexcept;
constexpr std::size_t count() const noexcept;
constexpr std::size_t size() const noexcept;
constexpr std::size_t max_size() const noexcept;
constexpr bitset& operator&= (const bitset& other) noexcept;
constexpr bitset& operator|= (const bitset& other) noexcept;
constexpr bitset& operator^= (const bitset& other) noexcept;
constexpr bitset operator~() const noexcept;
constexpr bitset& set() noexcept;
constexpr bitset& set(E pos, bool value = true);
constexpr bitset& reset() noexcept;
constexpr bitset& reset(E pos);
constexpr bitset& flip() noexcept;
friend constexpr bitset operator&(const bitset& lhs, const bitset& rhs) noexcept;
friend constexpr bitset operator|(const bitset& lhs, const bitset& rhs) noexcept;
friend constexpr bitset operator^(const bitset& lhs, const bitset& rhs) noexcept;
template<typename V = E>
constexpr explicit operator std::enable_if_t<magic_enum::detail::is_flags_v<V>, E>() const;
string to_string(char sep = '|') const;
string to_string(detail::raw_access_t,
char zero = '0',
char one = '1') const;
constexpr unsigned long long to_ullong(detail::raw_access_t raw) const;
constexpr unsigned long long to_ulong(detail::raw_access_t raw) const;
friend std::ostream& operator<<(std::ostream& o, const bitset& bs);
friend std::istream& operator>>(std::istream& i, bitset& bs);
}
-
STL like bitset for all enums.
-
Examples
constexpr magic_enum::containers::bitset<Color> color_bitset_red_green {Color::RED|Color::GREEN}; bool all = color_bitset_red_green.all(); // all -> false // Color::BLUE is missing bool test = color_bitset_red_green.test(Color::RED); // test -> true
auto color_bitset = magic_enum::containers::bitset<Color>(); color_bitset.set(Color::GREEN); color_bitset.set(Color::BLUE); std::string to_string = color_bitset.to_string(); // to_string -> "GREEN|BLUE"
template<typename E, typename CExprLess = std::less<E>>
class set {
constexpr set() noexcept = default;
template<typename InputIt>
constexpr set(InputIt first, InputIt last);
constexpr set(std::initializer_list<E> ilist);
template<typename V = E>
constexpr explicit set(std::enable_if_t<magic_enum::detail::is_flags_v<V>, E> starter);
constexpr set(const set&) noexcept = default;
constexpr set(set&&) noexcept = default;
constexpr set& operator=(const set&) noexcept = default;
constexpr set& operator=(set&&) noexcept = default;
constexpr set& operator=(std::initializer_list<E> ilist);
constexpr const_iterator begin() const noexcept;
constexpr const_iterator end() const noexcept;
constexpr const_iterator cbegin() const noexcept;
constexpr const_iterator cend() const noexcept;
constexpr const_reverse_iterator rbegin() const noexcept;
constexpr const_reverse_iterator rend() const noexcept;
constexpr const_reverse_iterator crbegin() const noexcept;
constexpr const_reverse_iterator crend() const noexcept;
constexpr bool empty() const noexcept;
constexpr size_type size() const noexcept;
constexpr size_type max_size() const noexcept;
constexpr void clear() noexcept;
constexpr std::pair<iterator,bool> insert(const value_type& value) noexcept;
constexpr std::pair<iterator,bool> insert(value_type&& value) noexcept;
constexpr iterator insert(const_iterator, const value_type& value) noexcept;
constexpr iterator insert(const_iterator hint, value_type&& value) noexcept;
template< class InputIt >
constexpr void insert(InputIt first, InputIt last) noexcept;
constexpr void insert(std::initializer_list<value_type> ilist) noexcept;
template<class... Args>
constexpr std::pair<iterator,bool> emplace(Args&&... args) noexcept;
template<class... Args>
constexpr iterator emplace_hint(const_iterator, Args&&... args) noexcept;
constexpr iterator erase(const_iterator pos) noexcept;
constexpr iterator erase(const_iterator first, const_iterator last) noexcept;
constexpr size_type erase(const key_type& key) noexcept;
template<class K, typename KC = key_compare>
constexpr std::enable_if_t<detail::is_transparent_v<KC>, size_type> erase(K&& x) noexcept;
void swap(set& other) noexcept;
constexpr size_type count(const key_type& key) const noexcept;
template<typename K, typename KC = key_compare>
constexpr std::enable_if_t<detail::is_transparent_v<KC>, size_type> count(const K& x) const;
constexpr const_iterator find(const key_type & key) const noexcept;
template<class K, typename KC = key_compare>
constexpr std::enable_if_t<detail::is_transparent_v<KC>, const_iterator> find(const K& x) const;
constexpr bool contains(const key_type& key) const noexcept;
template<typename K, typename KC = key_compare>
constexpr std::enable_if_t<detail::is_transparent_v<KC>, bool> contains(const K& x) const noexcept;
constexpr std::pair<const_iterator,const_iterator> equal_range(const key_type& key) const noexcept;
template<typename K, typename KC = key_compare>
constexpr std::enable_if_t<detail::is_transparent_v<KC>, std::pair<const_iterator,const_iterator>> equal_range(const K& x) const noexcept;
constexpr const_iterator lower_bound(const key_type& key) const noexcept;
template<typename K, typename KC = key_compare>
constexpr std::enable_if_t<detail::is_transparent_v<KC>, const_iterator> lower_bound(const K& x) const noexcept;
constexpr const_iterator upper_bound(const key_type& key) const noexcept;
template<typename K, typename KC = key_compare>
constexpr std::enable_if_t<detail::is_transparent_v<KC>, const_iterator> upper_bound(const K& x) const noexcept;
constexpr key_compare key_comp() const;
constexpr value_compare value_comp() const;
constexpr friend bool operator==(const set& lhs, const set& rhs) noexcept;
constexpr friend bool operator!=(const set& lhs, const set& rhs) noexcept;
constexpr friend bool operator<(const set& lhs, const set& rhs) noexcept;
constexpr friend bool operator<=(const set& lhs, const set& rhs) noexcept;
constexpr friend bool operator>(const set& lhs, const set& rhs) noexcept;
constexpr friend bool operator>=(const set& lhs, const set& rhs) noexcept;
template<typename Pred>
size_type erase_if(Pred pred);
}
-
STL like set for all enums.
-
Examples
constexpr magic_enum::containers::set color_set_filled = {Color::RED, Color::GREEN, Color::BLUE};
auto color_set = magic_enum::containers::set<Color>(); bool empty = color_set.empty(); // empty -> true color_set.insert(Color::GREEN); color_set.insert(Color::BLUE); color_set.insert(Color::RED); std::size_t size = color_set.size(); // size -> 3