4 ms·

Since memory is copied, it's really not clear to me what the advantage is of using value_ptr over just using values. Is it just about heap vs. stack?

• Eyas 9y ago
  I think its about recursive types/members, e.g. class Tree { Tree _left, _right; }; Won't compile because it has an infinite size. However class Tree { Tree *_left, *_right; }; Compiles, but the author contends that a more explicit description of the ownership semantics is better: class Tree { value_ptr<Tree> _left, _right; } This is also why `value_ptr` is different than `optional`.
  • waqf 9y ago
    I think you have to say something about the copy semantics too, because if you ignore those, value_ptr would be synonymous with unique_ptr. class Tree { Tree *_left, *_right; }; Tree y = x; makes a shallow copy. class Tree { unique_ptr<Tree> _left, _right; }; Tree y = x; doesn't compile, but class Tree { value_ptr<Tree> _left, _right; }; Tree y = x; makes a deep copy.
  • waynecochran 9y ago
    With value-ptr's would traversing the tree require making copies of examined nodes as you search? What would the tree_search method look like?
• deleted 9y ago
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