• 2 Posts
  • 3 Comments
Joined 1 year ago
cake
Cake day: December 3rd, 2023

help-circle
  • This week some more work was done on inheriteRS to support inheriting non-trait implementations of functions.

    Basically

    use inheriters::specialisations;
    
    specialisations!(
        struct Parent {
            attr1: u8,
        }
        impl Parent {
            fn from_parent(self) -> u8 { 8 }
            fn overridden(self) -> u8 { self.attr1 }
        }
        
        #[inherit(Child)]
        struct Child {
            attr2: u8,
        }
        impl Child {
            fn overridden(self) -> u8 { self.attr2 }
        }
    );
    

    results in

    struct Parent {
        attr1: u8,
    }
    impl Parent {
        fn from_parent(self) -> u8 { 8 }
        fn overridden(self) -> u8 { self.attr1 }
    }
    
    
    struct Child {
        attr1: u8, // new
        attr2: u8,
    }
    impl Child {
        fn from_parent(self) -> u8 { 8 } // new
        fn overridden(self) -> u8 { self.attr2 }
    }
    

    There might be some clean-up necessary code-wise and the README has to be expanded. But the project is well on its way to version 1! It’s a pity codeberg doesn’t have easy CI/CD yet nor domain hosting e.g inheriters.codeberg.io or something. So auto-formatting, testing, auto-tagging, etc. will have to come once I can convince myself to setup a VPS somewhere that hosts all that.



  • 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.