Simple counted pointer with variable like const access. More...

#include <Rep.h>

Inheritance diagram for VarPtr< _Rep >:

Public Member Functions
	VarPtr ()

	VarPtr (_Rep *ptr_r)

_Rep *	operator-> ()

const _Rep *	operator-> () const

_Rep &	operator* ()

const _Rep &	operator* () const

Public Member Functions inherited from BasicRepPtr
	operator const void * () const

Private Member Functions
_Rep *	ptr () const

Additional Inherited Members
Protected Member Functions inherited from BasicRepPtr
	BasicRepPtr ()

	BasicRepPtr (Rep *ptr)

	BasicRepPtr (const BasicRepPtr &rhs)

BasicRepPtr &	operator= (const BasicRepPtr &rhs)

	~BasicRepPtr ()

Rep *	repPtr () const

Detailed Description

template<typename _Rep>
class VarPtr< _Rep >

Simple counted pointer with variable like const access.

On construction and assignment it behaves like a pointer. I.e. a 'const VarPtr<_Tp>' is a '_Tp *const'.

But accessing _Tp (via operator-> or operator*) its constness is propagated to _Tp. I.e. 'VarPtr<_Tp>' behaves like a '_Tp *' while a 'const VarPtr<_Tp>' behaves as a 'const _Tp *'.

Used in some classes to hide implementation data from the interface:

class Foo
{
  class _Implementation;
  VarPtr<_Implementation> _impl;
  ...

All a VarPtr does, is preventing accidential access to nonconst implementation data from const interface methods. If such access is intended is has to be expressed by using a cost_cast.