zonbi 0.3.2

Type-Erase tools for non-`'static` types
Documentation 
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use std::collections::HashMap;

use zonbi::{AnyZonbi, Cage, Zonbi, ZonbiId};

#[derive(Debug, PartialEq)]
struct NonCopyI32(i32);

#[derive(Zonbi)]
struct MyStruct<'a> {
    val: &'a NonCopyI32,
}

fn main() {
    let a = NonCopyI32(42);

    with_zonbi(&a);
}

fn with_zonbi<'a>(a: &'a NonCopyI32) {
    let my_struct = MyStruct { val: a };

    let mut type_map: HashMap<ZonbiId, Box<dyn AnyZonbi<'a>>> = HashMap::new();
    let id = ZonbiId::of::<MyStruct>();

    type_map.insert(id, Box::new(Cage::new(my_struct)));

    let r: &MyStruct<'a> = type_map[&id].downcast_ref::<MyStruct<'a>>().unwrap();
    assert_eq!(r.val, &NonCopyI32(42));
    println!("{:?}", r.val);
}

// Try commenting the code out
// fn fails<'a>(a: &'a NonCopyI32) {
//     use std::any::{Any, TypeId};

//     let my_struct = MyStruct { val: a };

//     let mut type_map: HashMap<TypeId, Box<dyn Any>> = HashMap::new();
//     let id = TypeId::of::<MyStruct>();
//     type_map.insert(id, Box::new(my_struct));
// }