Macro hotdrink_rs::component_type

macro_rules! component_type {
    (
        $(#[$meta:meta])*
        $vis:vis enum $type_name:ident { $( $constr:ident ),* $(,)? }
    ) => { ... };
}

A macro for automatically generating an enum that has a variant for each type to use in a constraint system. It will also implement From and TryInto implementations for each of these variants.

Examples

#[derive(Debug, PartialEq)]
struct Foo;

// Generate the struct and impls
hotdrink_rs::component_type! {
    #[derive(Debug, PartialEq)]
    enum MyType {
      i32,
      f64,
      Foo
    }
}

// Create instance of MyType
let mt: MyType = MyType::from(Foo);
assert_eq!(mt, MyType::Foo(Foo));

// Try to convert it to f32
let x: Result<f64, ()> = mt.try_into();
assert_eq!(x, Err(()));

// Try to convert a MyType to i32
let y: Result<i32, ()> = MyType::from(23).try_into();
assert_eq!(y, Ok(23));