• Wappen@lemmy.world
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    27 days ago

    Equality in rust is value equality per default, that’s what these traits are for. If you want to check pointer equality you’d use the std::ptr::eq function to check if two pointers are equal, which is rather rare in practice. You can also implement the PartialEq trait yourself if you need custom equality checks.

    • brisk@aussie.zone
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      27 days ago

      I worked on software at one point that had at it’s core a number of “modes” that it switched between. It was, at the time, in the process of migrating from enums and switch/case trees to an inheritance based system.

      In practice this meant there was a single instance of “Mode” for each mode which used pointer equality to switch/case on modes like an enum.

      To add a new mode (that did nothing) I think I had to change about 6 different places.

      • Dhs92@programming.dev
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        27 days ago

        Not really related to the pointer thing, but Rust also has pattern matching based on Enums, as they’re actually sum-types and not just numbers