nemo::IntrusiveCowSupport< T, CA > Class Template Reference

Generic utility class for "copy-on-write" (COW) data types. More...

#include <IntrusiveCowSupport.h>

Public Member Functions
	IntrusiveCowSupport (T *t)
	IntrusiveCowSupport (const IntrusiveCowSupport< T, CA > &p)
IntrusiveCowSupport &	operator= (const IntrusiveCowSupport< T, CA > &rhs)
virtual	~IntrusiveCowSupport ()
const T *	operator-> () const
void	detach ()

Detailed Description

template<class T, class CA = CopyAllocator<T>>
class nemo::IntrusiveCowSupport< T, CA >

Generic utility class for "copy-on-write" (COW) data types.

Altough it has pointer semantics, this class is NOT a full blown, automatic COW pointer. Rather it can be used in some class C, that supports COW, internally.

The class C is responsible for calling the detach() function before C makes any change in the data T. detach() will then automatically create a data copy of T is more than one reference point to that data.

There are several requirements on the type T:

T must be copy-constructable.
There must be an operation void intrusive_ptr_add_ref(T*)
There must be an operation void intrusive_ptr_release(T*)
There must be an operation bool unique(T*) The easiest way to achieve the last three requirments is to let T inherit from nemo::IntrusiveCounted<T>.

C is furthermore responsible for not assigning null-pointers to IntrusiveCowSupport.

The second type argument CA can be used to customize the data-copy procedure that is used in the detach routine. See CopyAllocator.

Definition at line 52 of file IntrusiveCowSupport.h.