Re: [Boost-users] [Graph] Polymorphic properties

Renaud Detry skrev:

Hi,

I have a question related to Boost.Graph bundle properties when there are two distinct vertex/edge types.

1b.- Instead of boost::shared_ptr, boost::ptr_array could be used. The property instances are cloned when the ptr_array is copied.

2.- VertexProperties is a simple class that contains a type enum (VA or VB), and an index that identifies a data element in an external container. There would be two external containers, one containing VA data, the other for VB data.

The advantage of (1b) is automatic memory management -- when a vertex is deleted, its properties also die. With (2), properties have to be manually deleted when an vertex is removed. On the other hand, (2) is a bit more simple to serialize, since there's no dynamic allocation (i.e. not on the user side) and no polymorphism (no BOOST_CLASS_EXPORT_GUID...).

My questions are:

- In (1b), will boost::ptr_array provide the expected behavior, i.e. that of a clone_ptr?

Depends on what the behavior of clone_ptr is. But, ptr_array is cloned when the copy-constructor or assigment operator is called, if that's what you're asking. -Thorsten