Opt< const T & > Class Template Reference

#include <optional.h>

Detailed Description

template<typename T>
class maxon::Opt< const T & >

Specialization to store const lvalue references, which only uses a single pointer internally. This can be used to treat pointers that may be null as optional references for more descriptive interfaces.

Public Types
using	ValueType = const T &
template<typename SUPER >
using	ResultFunctions = maxon::details::ResultOptFunctions< SUPER >

Public Member Functions
	Opt ()
MAXON_IMPLICIT	Opt (NO_VALUE_TYPE)
	Opt (const Opt &src)
Opt &	operator= (const Opt &src)
MAXON_IMPLICIT	Opt (const T &value)
MAXON_IMPLICIT	Opt (const T *valuePtr)
Bool	HasValue () const
	operator Bool ()
	operator Bool () const
Result< const T & >	GetValue () const
const T &	GetValueOr (const T &defaultValue) const
T	GetValueOr (T &&defaultValue) const
const T &	GetValueOrNull () const
const T *	operator-> () const
const T &	operator* () const
const T *	ToPointer () const
	operator const T * ()

Private Member Functions
MAXON_ATTRIBUTE_FORCE_INLINE void	CheckValue () const

Private Attributes
const T *	_dataPtr

Member Typedef Documentation

ValueType

using ValueType = const T&

ResultFunctions

using ResultFunctions = maxon::details::ResultOptFunctions<SUPER>

Constructor & Destructor Documentation

Opt() [1/5]

Opt

(

)

Default constructor. Creates an Opt with no value.

Opt() [2/5]

MAXON_IMPLICIT Opt

(

NO_VALUE_TYPE

)

Explicit construction with NO_VALUE. Has the same effect as the default constructor.

Opt() [3/5]

Opt

(

const Opt< const T & > &

src

)

Copy constructor.

Opt() [4/5]

MAXON_IMPLICIT Opt

(

const T &

value

)

Constructs from const reference.

Opt() [5/5]

MAXON_IMPLICIT Opt

(

const T *

valuePtr

)

Constructs from raw pointer.

Member Function Documentation

operator=()

Opt& operator=

(

const Opt< const T & > &

src

)

Copy assignment.

HasValue()

Bool HasValue

(

)

const

Returns true if this object contains a value.

operator Bool() [1/2]

operator Bool ( )

explicit

operator Bool() [2/2]

operator Bool ( ) const

explicit

GetValue()

Result<const T&> GetValue

(

)

const

Returns the contained value, or IllegalState error if object contained no value.

GetValueOr() [1/2]

const T& GetValueOr

(

const T &

defaultValue

)

const

Returns the contained value, or a default value if object contained no value.

GetValueOr() [2/2]

T GetValueOr

(

T &&

defaultValue

)

const

Returns the contained value, or a default value if object contained no value.

GetValueOrNull()

const T& GetValueOrNull

(

)

const

Returns the contained value, or a null value if object contained no value.

operator->()

const T* operator->

(

)

const

Returns a pointer to the contained value. Results in undefined behavior if object contained no value.

operator*()

const T& operator*

(

)

const

Returns a reference to the contained value. Results in undefined behavior if object contained no value.

ToPointer()

const T* ToPointer

(

)

const

operator const T *()

operator const T *

(

)

Converts the optional reference to a raw pointer. This is supported for interoperability with legacy code.

CheckValue()

MAXON_ATTRIBUTE_FORCE_INLINE void CheckValue ( ) const

private

Member Data Documentation

_dataPtr

const T* _dataPtr

private