Re: Pointers in const containers
The first obvious question is, why do you have a container of
pointers, and not plain objects? Since it's a tree, you shouldn't need
to have several parent nodes point to the same child node.
Pointers are required due to language constraints. It is not
possible to write:
struct tree_node {
/* ... */
private:
std::vector<tree_node> children_;
};
(although some compilers allow it) because at the place of declaration
of children_ tree_node is incomplete type and incomplete types cannot
be used with STL containers.
And obviously parent has to be stored as a pointer (reference will
not do because of root node and possibility of moving nodes).
If you really need the pointers, though, then you might want to look
at Boost pointer container library, and in particular,
boost::ptr_vector. It implements full ownership semantics for the
pointer elements it contains, and therefore, propagates constness in
all member-access operations.
Looks promising. Thanks!
Adam Badura
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