Hi rustaceans! What are you working on this week? Did you discover something new, you want to share?

  • tinkralge@programming.dev
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    3 months ago

    Working on some form of inheritance in rust. It’s my first foray into procedural macros and so far it’s fun. The idea is quite simple: generate structs with common attributes (and eventually functions) instead writing them yourself.

    use inheriters::specialisations;
    
    specialisations!(
        struct Parent {
            attr1: u8,
        }
        #[inherit(Child)]
        struct Child {
            attr2: u8,
        }
    );
    

    becomes

    struct Parent {
        attr1: u8,
    }
    struct Child {
        attr1: u8,
        attr2: u8,
    }
    

    not

    struct Parent {
        attr1: u8,
    }
    struct Child {
        attr1: u8,
        parent: Parent,
    }
    

    The latter leads to indirection which I’m not a fan of.

    Last week I squashed one bug on the order of attributes according to inheritance. In the example above attr2 was coming before attr1. A feature is nearly done to exclude the Parent from the output and only output the child. That’s useful for parents that just serve as holders for shared attributes.

    The goal for v1 was to also support basic inheritance of implementations: Parent has an impl block, then that block is copied for the Child. Not sure yet if I’ll implement overrides in v1 or v2. Overrides being if Parent implements do_something() and Child does too, then the implementation of Parent is not copied into the impl block.
    That’s what I’ll try to tackle in the coming weeks.