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Static vector of shared_ptr

This is a discussion on Static vector of shared_ptr within the C++ Programming forums, part of the General Programming Boards category; Originally Posted by King Mir That doesn't help you move actors in the grid. But a move is not a ...

  1. #31
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    Quote Originally Posted by King Mir View Post
    That doesn't help you move actors in the grid.
    But a move is not a copy correct? If I move a unique_ptr from one location to another inside a container, that does not entail copy right?

    If this will never work I am happy to use auto_ptr for this example even though their copy is messed up in comparison.

  2. #32
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    Moving a pointer on the grid would ideally look something like this:

    Code:
    grid[move_to_x][move_to_y] = grid[move_from_x][move_from_y];
    grid[move_from_x][move_from_y] = 0;
    That's how it'd look with dumb pointers. But, you can't do that with unique_ptrs, because the correct assignment operator is not defined. Shared pointers would actually work. auto_ptr is a perfect fit though, because auto_ptr will do both steps in the assignment; to move an auto_ptr you'd just do this:
    Code:
    grid[move_to_x][move_to_y] = grid[move_from_x][move_from_y];
    That also illustrates why auto_ptr is weird and bad in general. That's not behavior you'd expect from a normal pointer. But it is what you want here.
    It is too clear and so it is hard to see.
    A dunce once searched for fire with a lighted lantern.
    Had he known what fire was,
    He could have cooked his rice much sooner.

  3. #33
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    Quote Originally Posted by King Mir View Post
    Moving a pointer on the grid would ideally look something like this:

    Code:
    grid[move_to_x][move_to_y] = grid[move_from_x][move_from_y];
    grid[move_from_x][move_from_y] = 0;
    That's how it'd look with dumb pointers. But, you can't do that with unique_ptrs, because the correct assignment operator is not defined. Shared pointers would actually work. auto_ptr is a perfect fit though, because auto_ptr will do both steps in the assignment; to move an auto_ptr you'd just do this:
    Code:
    grid[move_to_x][move_to_y] = grid[move_from_x][move_from_y];
    That also illustrates why auto_ptr is weird and bad in general. That's not behavior you'd expect from a normal pointer. But it is what you want here.
    Very nice and I appreciate that perspective. By your post, I would say auto_ptr still has use when applicable and I will try all the solutions given to this thread.

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