3 ms·

You can track all of this (things like Rc or Arc do) except move. Relative pointers are possible, depending on what you mean. Making this safe (e.g. preventing

• dataflow 3y ago
  > You can track all of this (things like Rc or Arc do) except move. Which means you can't track this. Tracking moves is fundamental here. > Relative pointers are possible, depending on what you mean. Pretty sure they're not possible in the sense I mean, for the same reason as above - you need custom moves for this. I'm referring to a pointer (not an offset; a pointer) that automatically adjusts itself when copied or moved. So that it always points somewhere N blocks before/after itself. These are just two examples, to get the point across that Rust actually lacks some capabilities (since somehow that surprises people). You can find more.
  • remram 3y ago
    > Tracking moves is fundamental here. I mean, arguably. If it is fundamental for your hypothetical use case, then sure, but this is not required for a lot of use cases, like smart pointers.
    • dataflow 3y ago
      > this is not required for a lot of use cases, like smart pointers. Nobody claimed otherwise. The question was what things Rust can't do, not what it can do.
      • remram 3y ago
        Yeah, that's fair. You can't do it, not even using horrible hacks.