2011/4/8 Jim Hodapp
<james.hodapp@gmail.com>
I am using a ptr_vector<MyAbstractType> in a class called Container to
store pointers to derived types inherited from MyAbstractType. In my
Container class, I want to have a member function which returns the
ptr_vector<MyAbstractType>. First, am I better off modelling this
"getter" as an iterator over this ptr_vector or is it proper to return
the ptr_vector itself? Right now, when trying to return the ptr_vector
itself (a copy of it) I am getting an error:
"/usr/include/boost/ptr_container/clone_allocator.hpp:34: error:
cannot allocate an object of abstract type 'MyAbstractType'
The function prototype for the getter is: ptr_vector<MyAbstractType>
GetDestinations() const
Is ptr_vector trying to make a copy of each MyAbstractType contained
instead of copying the pointer value itself? This would indicate that
I need a get() type method for ptr_vector like what a scoped_ptr has.
Any recommendations on how to design this situation?
Thanks,
Jim
I think you should read about the cloneable concept in ptr_container docs, which kicks in when you make a copy of a pointer container.
Typically (if I remember correctly) you need to overload make_clone, and delete_clone for your MyAbstractType. Or you may write a clone allocator, and use ptr_vector<MyAbstractType,MyCloneAllocator>.
Regards,
Kris