The name SmartPtrIRCCOW stands for
Smart Pointer with Intrusive Reference Count and Copy-on-write.
(or Lazy Copy).
It is very similar to SmartPtrIRC, where two cooperating classes
are SmartPtrIRCCOW and IntrusiveReferenceCountCOWBase, but
also allows assigning, copying, and modifying.
The abstract class IntrusiveReferenceCountCOWBase inherits from
IntrusiveReferenceCount (see documentation for SmartPtrIRC),
with an additional pure virtual function myClone which must be
implemented by the concrete class returning a deep copy of the object.
The template class SmartPtrIRCCOW<T> is implemented with one data member:
private: SmartPtrIRC<T> mySmartPtr;
Which does (almost) all the work. The core for the copy-on-write behaviour is the member function:
private: void myDetach()
which (if necessary) makes a new deep copy with reference count 1 and decrements the reference count of the original object.
2010
0.9938 first version July 2010 (experimental)