mgutility::optional< T > Class Template Reference

A class template that provides optional (nullable) objects. More...

#include <optional.hpp>

Public Member Functions
MGUTILITY_CNSTXPR	optional (nullopt_t &)
	Constructs an empty optional.
MGUTILITY_CNSTXPR	optional ()
	Constructs an empty optional.
template<typename... Args>
MGUTILITY_CNSTXPR	optional (Args &&...args)
	Constructs an optional with a value.
MGUTILITY_CNSTXPR	optional (T &&value)
	Constructs an optional with a value.
MGUTILITY_CNSTXPR	optional (const optional &other)
	Copy constructor.
MGUTILITY_CNSTXPR	optional (optional &&other)
	Move constructor.
	~optional ()
	Destructor.
MGUTILITY_CNSTXPR optional &	operator= (const optional &other)
	Copy assignment operator.
MGUTILITY_CNSTXPR optional &	operator= (optional &&other)
	Move assignment operator.
MGUTILITY_CNSTXPR void	swap (optional &&other)
	Swaps the contents of this optional with another.
MGUTILITY_CNSTXPR T &	operator* ()
	Dereferences the stored value.
MGUTILITY_CNSTXPR T &	operator* () const
	Dereferences the stored value (const version).
MGUTILITY_CNSTXPR T &	value ()
	Accesses the stored value.
MGUTILITY_CNSTXPR T &	value () const
	Accesses the stored value (const version).
MGUTILITY_CNSTXPR T	value_or (T &&value)
	Returns the stored value or a default value if empty.
MGUTILITY_CNSTXPR T	value_or (T &&value) const
	Returns the stored value or a default value if empty (const version).
MGUTILITY_CNSTXPR T	value_or (const T &value)
	Returns the stored value or a default value if empty.
MGUTILITY_CNSTXPR T	value_or (const T &value) const
	Returns the stored value or a default value if empty (const version).
MGUTILITY_CNSTXPR void	emplace (T value)
	Constructs the value in-place.
template<typename... Args>
MGUTILITY_CNSTXPR void	emplace (Args &&...args)
	Constructs the value in-place with arguments.
MGUTILITY_CNSTXPR bool	has_value () const
	Checks if the optional has a value.
template<typename U = T, detail::enable_if_t<!std::is_destructible< U >::value, bool > = true>
MGUTILITY_CNSTXPR void	reset ()
	Resets the optional, making it empty.
template<typename U = T, detail::enable_if_t< std::is_destructible< T >::value, bool > = true>
MGUTILITY_CNSTXPR void	reset ()
	Resets the optional, making it empty.
MGUTILITY_CNSTXPR	operator bool ()
	Checks if the optional has a value.

Detailed Description

template<typename T>
class mgutility::optional< T >

A class template that provides optional (nullable) objects.

Template Parameters

T	The type of the value.

Constructor & Destructor Documentation

optional() [1/4]

template<typename T >

template<typename... Args>

MGUTILITY_CNSTXPR mgutility::optional< T >::optional ( Args &&... args )

inline

Constructs an optional with a value.

Template Parameters

Args	The types of the arguments.

Parameters

args	The arguments to construct the value.

optional() [2/4]

template<typename T >

MGUTILITY_CNSTXPR mgutility::optional< T >::optional ( T && value )

inline

Constructs an optional with a value.

Parameters

value

The value to initialize with.

optional() [3/4]

template<typename T >

MGUTILITY_CNSTXPR mgutility::optional< T >::optional ( const optional< T > & other )

inline

Copy constructor.

Parameters

other

The other optional to copy.

optional() [4/4]

template<typename T >

MGUTILITY_CNSTXPR mgutility::optional< T >::optional ( optional< T > && other )

inline

Move constructor.

Parameters

other

The other optional to move.

Member Function Documentation

emplace() [1/2]

template<typename T >

template<typename... Args>

MGUTILITY_CNSTXPR void mgutility::optional< T >::emplace ( Args &&... args )

inline

Constructs the value in-place with arguments.

Template Parameters

Args	The types of the arguments.

Parameters

args	The arguments to construct the value.

emplace() [2/2]

template<typename T >

MGUTILITY_CNSTXPR void mgutility::optional< T >::emplace ( T value )

inline

Constructs the value in-place.

Parameters

value

The value to emplace.

has_value()

template<typename T >

MGUTILITY_CNSTXPR bool mgutility::optional< T >::has_value ( ) const

inline

Checks if the optional has a value.

Returns

True if the optional has a value, otherwise false.

operator bool()

template<typename T >

MGUTILITY_CNSTXPR mgutility::optional< T >::operator bool ( )

inline

Checks if the optional has a value.

Returns

True if the optional has a value, otherwise false.

operator*() [1/2]

template<typename T >

MGUTILITY_CNSTXPR T & mgutility::optional< T >::operator* ( )

inline

Dereferences the stored value.

Returns

A reference to the stored value.

operator*() [2/2]

template<typename T >

MGUTILITY_CNSTXPR T & mgutility::optional< T >::operator* ( ) const

inline

Dereferences the stored value (const version).

Returns

A reference to the stored value.

operator=() [1/2]

template<typename T >

MGUTILITY_CNSTXPR optional & mgutility::optional< T >::operator= ( const optional< T > & other )

inline

Copy assignment operator.

Parameters

other

The other optional to copy.

Returns

A reference to this optional.

operator=() [2/2]

template<typename T >

MGUTILITY_CNSTXPR optional & mgutility::optional< T >::operator= ( optional< T > && other )

inline

Move assignment operator.

Parameters

other

The other optional to move.

Returns

A reference to this optional.

swap()

template<typename T >

MGUTILITY_CNSTXPR void mgutility::optional< T >::swap ( optional< T > && other )

inline

Swaps the contents of this optional with another.

Parameters

other

The other optional to swap with.

value() [1/2]

template<typename T >

MGUTILITY_CNSTXPR T & mgutility::optional< T >::value ( )

inline

Accesses the stored value.

Returns

A reference to the stored value.

Exceptions

bad_optional_access

if the optional has no value.

value() [2/2]

template<typename T >

MGUTILITY_CNSTXPR T & mgutility::optional< T >::value ( ) const

inline

Accesses the stored value (const version).

Returns

A reference to the stored value.

Exceptions

bad_optional_access

if the optional has no value.

value_or() [1/4]

template<typename T >

MGUTILITY_CNSTXPR T mgutility::optional< T >::value_or ( const T & value )

inline

Returns the stored value or a default value if empty.

Parameters

value

The default value to return if empty.

Returns

The stored value or the default value.

value_or() [2/4]

template<typename T >

MGUTILITY_CNSTXPR T mgutility::optional< T >::value_or ( const T & value ) const

inline

Returns the stored value or a default value if empty (const version).

Parameters

value

The default value to return if empty.

Returns

The stored value or the default value.

value_or() [3/4]

template<typename T >

MGUTILITY_CNSTXPR T mgutility::optional< T >::value_or ( T && value )

inline

Returns the stored value or a default value if empty.

Parameters

value

The default value to return if empty.

Returns

The stored value or the default value.

value_or() [4/4]

template<typename T >

MGUTILITY_CNSTXPR T mgutility::optional< T >::value_or ( T && value ) const

inline

Returns the stored value or a default value if empty (const version).

Parameters

value

The default value to return if empty.

Returns

The stored value or the default value.

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The documentation for this class was generated from the following file:

• /home/runner/work/enum_name/enum_name/include/mgutility/std/optional.hpp