ReferenceWrapper< TYPE > Class Template Reference

#include <referencewrapper.h>

Detailed Description

template<typename TYPE>
class maxon::ReferenceWrapper< TYPE >

Wraps a pointer, but enforces reference semantics for assignment and hence cannot be null. Can be used just like a normal pointer (e.g. operator -> to call methods). However, even if it works, the use of operator * is discouraged and reference semantics should be used instead. Note that a ReferenceWrapper instance can be converted implicitly to a reference or a pointer of the same type (but not the other way around!). Similar in function to std::reference_wrapper<TYPE>.

Float value1 = 5.0;
Float value2 = 10.0;
 
ReferenceWrapper<Float> valueRef;               // Doesn't compile! A reference cannot be null.
ReferenceWrapper<Float> valueRef = value1;      // Doesn't compile! To improve readability, implicit conversions are disabled and an explicit call to Ref or CRef functions is enforced (as opposed to std::reference_wrapper<TYPE>).
ReferenceWrapper<Float> valueRef = Ref(value1); // valueRef now points to value1
ReferenceWrapper<Float> valueRef(Ref(value1));  // valueRef now points to value1 (equivalent to the previous statement)
 
valueRef = 0.0;         // value1 now equals 0.0
valueRef = value2;      // value1 now equals 10.0
valueRef = Ref(value2); // valueRef now points to value2
valueRef = 0.0;         // value2 now equals 0.0
*valueRef = 5.0;        // value2 now equals 5.0. Works, but isn't recommended, because valueRef now looks like a pointer.

Public Member Functions
	ReferenceWrapper ()=default
	ReferenceWrapper (const ReferenceWrapper &) noexcept=default
ReferenceWrapper &	operator= (const ReferenceWrapper &) noexcept=default
void	operator= (const TYPE &value)
UInt	GetHashCode () const
Bool	IsEqual (const ReferenceWrapper &ref) const
	operator TYPE * () const noexcept
	operator TYPE & () const noexcept
TYPE *	operator-> () const noexcept
TYPE **	operator& () noexcept

Static Public Member Functions
static ReferenceWrapper< TYPE >	Create (TYPE &val) noexcept
static ReferenceWrapper< const TYPE >	CreateConst (TYPE &val) noexcept

Private Member Functions
MAXON_IMPLICIT	ReferenceWrapper (TYPE &ref) noexcept
MAXON_IMPLICIT	ReferenceWrapper (TYPE &&)=delete

Private Attributes
TYPE *	_ptr

Constructor & Destructor Documentation

ReferenceWrapper() [1/4]

MAXON_IMPLICIT ReferenceWrapper ( TYPE &  ref )

privatenoexcept

ReferenceWrapper() [2/4]

MAXON_IMPLICIT ReferenceWrapper ( TYPE &&  )

privatedelete

ReferenceWrapper() [3/4]

ReferenceWrapper ( )

default

ReferenceWrapper() [4/4]

ReferenceWrapper ( const ReferenceWrapper< TYPE > &  )

defaultnoexcept

Member Function Documentation

Create()

static ReferenceWrapper<TYPE> Create ( TYPE &  val )

staticnoexcept

CreateConst()

static ReferenceWrapper<const TYPE> CreateConst ( TYPE &  val )

staticnoexcept

operator=() [1/2]

ReferenceWrapper& operator= ( const ReferenceWrapper< TYPE > &  )

defaultnoexcept

operator=() [2/2]

void operator=

(

const TYPE &

value

)

Used to change the value of the referenced object.

GetHashCode()

UInt GetHashCode

(

)

const

Hash function (for maxon::HashMap compatibility).

IsEqual()

Bool IsEqual

(

const ReferenceWrapper< TYPE > &

ref

)

const

Comparison function (for maxon::HashMap compatibility).

operator TYPE *()

operator TYPE * ( ) const

noexcept

Implicit conversion to a raw pointer type. Makes it possible to pass the object directly to functions like Function(TYPE* t).

Returns

The internal pointer. The AutoAlloc instance owns the pointed object.

operator TYPE &()

operator TYPE & ( ) const

noexcept

Implicit conversion to reference type. Makes it possible to pass the object directly to functions like Function(TYPE& t).

Returns

The dereferenced pointer.

operator->()

TYPE* operator-> ( ) const

noexcept

Used for calls like referenceWrapper->Function().

Returns

The internal pointer.

operator&()

TYPE** operator& ( )

noexcept

Used for expressions like &referenceWrapper. Extracts a pointer to the internal pointer.

Note

This means that it is impossible to get the address of the actual ReferenceWrapper instance.

Returns

A pointer to the internal pointer.

Member Data Documentation

_ptr

TYPE* _ptr

private