gf::Singleton< T > Class Template Reference

A singleton that wraps a pointer provided by a storage. More...

#include <gf/Singleton.h>

Public Member Functions
	Singleton ()
	Default constructor. More...
	Singleton (const Singleton &)=delete
	Deleted copy constructor. More...
	Singleton (Singleton &&)=delete
	Deleted move constructor. More...
Singleton &	operator= (const Singleton &)=delete
	Deleted copy assignment. More...
Singleton &	operator= (Singleton &&)=delete
	Deleted move assignment. More...
T &	operator() ()
	Access the singleton. More...
void	reset () noexcept
	Reset the singleton. More...
bool	isValid () const noexcept
	Check if the singleton has been initialized. More...

Detailed Description

template<typename T>
class gf::Singleton< T >

A singleton that wraps a pointer provided by a storage.

This class should be used with a global variable. It acts as an access to a singleton which storage is provided by a gf::SingletonStorage<T>.

gf::Singleton<Foo> gFoo;

int main() {
   gf::SingletonStorage<Foo> fooStorage(gFoo);

   gFoo().bar();
}

See also

gf::SingletonStorage

Constructor & Destructor Documentation

template<typename T>

gf::Singleton< T >::Singleton ( )

inline

Default constructor.

It initialize the underlying pointer to nullptr. The actual initialization is done when the storage is allocated.

template<typename T>

gf::Singleton< T >::Singleton ( const Singleton< T > &  )

delete

Deleted copy constructor.

template<typename T>

gf::Singleton< T >::Singleton ( Singleton< T > &&  )

delete

Deleted move constructor.

Member Function Documentation

template<typename T>

bool gf::Singleton< T >::isValid ( ) const

inlinenoexcept

Check if the singleton has been initialized.

Returns

True if the singleton is valid

template<typename T>

T& gf::Singleton< T >::operator() ( )

inline

Access the singleton.

The access of the singleton must be done after a storage has been provided. Otherwise, the behaviour is undefined (and may result in a crash).

Returns

a reference to the stored singleton

template<typename T>

Singleton& gf::Singleton< T >::operator= ( const Singleton< T > &  )

delete

Deleted copy assignment.

template<typename T>

Singleton& gf::Singleton< T >::operator= ( Singleton< T > &&  )

delete

Deleted move assignment.

template<typename T>

void gf::Singleton< T >::reset ( )

inlinenoexcept

Reset the singleton.

After a call to this function, the singleton must be accessed anymore.