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Comment by cgrealy | Hacker News Reader

>std::shared_ptr means I don't have to manage any memory; no more new/delete! (But try as I might to understand std::unique_ptr, I'm just not there yet.)

Eh? unique_ptr is just a scoped resource. You create a thing (or take ownership of said thing) and it gets deleted when it goes out of scope. Am I missing something?

It should be the first thing you reach for if you need to dynamically create an object (certainly way before shared_ptr).

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A simple variable would be a scoped resource, unique_ptr can be transferred.

    {
       RAII file = ....;
       // do stuff
    } // file is no longer open

    unique_ptr<RAII> outer_ptr;
    {
       unique_ptr<RAII> file = make_unique(...);
       // do stuff
       outer_ptr = file;
    } // resource still open

Your “RAII“ object can also be transferred if it supports move semantics (it really should). Both classes hold a unique resource (a file handle resp. a heap allocated object) that can be moved but not copied and the resource gets freed when the variable goes out of scope.

Yeah, I’m aware of that. I still don’t think it adds much to the complexity of unique_pet though.

It’s certainly less complicated than its ancestor auto_ptr.

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