G3D::lazy_ptr< T > Class Template Reference

Provides a level of indirection for accessing objects to allow computing them on demand or extending them with metadata without subclassing the object itself. More...

Public Member Functions
	lazy_ptr ()
	Creates a nullptr lazy pointer. More...
	lazy_ptr (nullptr_t)
	lazy_ptr (const std::function< shared_ptr< T >(void)> &resolve)
	Creates a lazy_ptr from a function that will create the object. More...
	lazy_ptr (const shared_ptr< T > &object)
	Creates a lazy_ptr for an already-resolved object. More...
template<class S >
	lazy_ptr (const shared_ptr< S > &object)
	Creates a lazy_ptr for an already-resolved object. More...
bool	isNull () const
	Is the proxy itself a null pointer. More...
bool	operator!= (const lazy_ptr< T > &other) const
const T &	operator* () const
	Invokes resolve. More...
T &	operator* ()
	Invokes resolve. More...
const T *	operator-> () const
	Invokes resolve. More...
T *	operator-> ()
	Invokes resolve. More...
bool	operator== (const lazy_ptr< T > &other) const
const shared_ptr< T >	resolve () const
	Returns a pointer to a T or a nullptr pointer. More...
shared_ptr< T >	resolve ()
	Returns a pointer to a T or a nullptr pointer. More...
bool	resolved () const
	True if this object can be resolved() without triggering any evaluation. More...

Detailed Description

template<class T>
class G3D::lazy_ptr< T >

Provides a level of indirection for accessing objects to allow computing them on demand or extending them with metadata without subclassing the object itself.

For example, lazy loading of files.

Useful for implementing lazy loading, for example, as done by ArticulatedModel::lazyCreate:

lazy_ptr<ArticulatedModel>([specification, name]{ return ArticulatedModel::create(specification, name); });

Analogous to shared_ptr and weak_ptr. Copies of lazy_ptrs retain the same underlying object, so it will only be resolved once.

Threadsafe.

Constructor & Destructor Documentation

lazy_ptr() [1/5]

template<class T>

G3D::lazy_ptr< T >::lazy_ptr ( )

inline

Creates a nullptr lazy pointer.

lazy_ptr() [2/5]

template<class T>

G3D::lazy_ptr< T >::lazy_ptr ( nullptr_t  )

inline

lazy_ptr() [3/5]

template<class T>

G3D::lazy_ptr< T >::lazy_ptr ( const std::function< shared_ptr< T >(void)> &  resolve )

inline

Creates a lazy_ptr from a function that will create the object.

lazy_ptr() [4/5]

template<class T>

G3D::lazy_ptr< T >::lazy_ptr ( const shared_ptr< T > &  object )

inline

Creates a lazy_ptr for an already-resolved object.

lazy_ptr() [5/5]

template<class T>

template<class S >

G3D::lazy_ptr< T >::lazy_ptr ( const shared_ptr< S > &  object )

inline

Creates a lazy_ptr for an already-resolved object.

Member Function Documentation

isNull()

template<class T>

bool G3D::lazy_ptr< T >::isNull ( ) const

inline

Is the proxy itself a null pointer.

Referenced by G3D::isNull(), G3D::notNull(), G3D::lazy_ptr< T >::operator==(), G3D::lazy_ptr< T >::resolve(), and G3D::lazy_ptr< T >::resolved().

operator!=()

template<class T>

bool G3D::lazy_ptr< T >::operator!= ( const lazy_ptr< T > &  other ) const

inline

operator*() [1/2]

template<class T>

const T& G3D::lazy_ptr< T >::operator* ( ) const

inline

Invokes resolve.

If you intend to use multiple dereferences, it is faster to invoke resolve() once and store the shared_ptr.

operator*() [2/2]

template<class T>

T& G3D::lazy_ptr< T >::operator* ( )

inline

Invokes resolve.

If you intend to use multiple dereferences, it is faster to invoke resolve() once and store the shared_ptr.

operator->() [1/2]

template<class T>

const T* G3D::lazy_ptr< T >::operator-> ( ) const

inline

Invokes resolve.

If you intend to use multiple dereferences, it is faster to invoke resolve() once and store the shared_ptr.

operator->() [2/2]

template<class T>

T* G3D::lazy_ptr< T >::operator-> ( )

inline

Invokes resolve.

If you intend to use multiple dereferences, it is faster to invoke resolve() once and store the shared_ptr.

operator==()

template<class T>

bool G3D::lazy_ptr< T >::operator== ( const lazy_ptr< T > &  other ) const

inline

resolve() [1/2]

template<class T>

const shared_ptr<T> G3D::lazy_ptr< T >::resolve ( ) const

inline

Returns a pointer to a T or a nullptr pointer.

If there are multiple levels of proxies, then this call resolves all of them.

Referenced by G3D::lazy_ptr< T >::operator*(), and G3D::lazy_ptr< T >::operator->().

resolve() [2/2]

template<class T>

shared_ptr<T> G3D::lazy_ptr< T >::resolve ( )

inline

Returns a pointer to a T or a nullptr pointer.

If there are multiple levels of proxies, then this call resolves all of them.

resolved()

template<class T>

bool G3D::lazy_ptr< T >::resolved ( ) const

inline

True if this object can be resolved() without triggering any evaluation.