Macro typemap

macro_rules! typemap {
    { $struct:ident =>
        $( $num:tt $ty:ty ),* $(,)?
    } => { ... };
}

A really bad way to genericize struct fields.

This abomination lets you create a struct with one field per type, accessible through as_ref(). Internally this is just a tuple, so there is the caveat that you need to manually specify the index of each “field”.

typemap! { SetOfSomeObjects =>
    0 SomeBindGroupLayoutOne,
    1 SomeOtherBindGroupTwo,
    2 EvenABuffer,
    3 AndHeresAPipeline,
    4 f32,
}

let set_of_some_objects = SetOfSomeObjects(
    SomeBindGroupLayoutOne::new(),
    ...
);

let buffer: EvenABuffer = set_of_some_objects.as_ref();
let pipeline: AndHeresAPipeline = set_of_some_objects.as_ref();