Useless ECS in Rust

I just wanted to understand how downcasting can be implemented. So I created this.

What

It has a World struct that contains all entities and storages. Each entity is simply Entity(u32) and each storage is stored in a HashMap.

In the HashMap, TypeId is used as key and the value is Box<dyn Storage>. The dyn Storage can be downcasted to a concrete storage StorageImpl<C>, where C: Component + 'static.

You can then get (imm)mutable access to storages and components.

Removing entities is not yet implemented.

How can I use it in my project?

It's best if you don't.