Struct orzir_core::Caster

pub struct Caster<T: ?Sized + 'static> { /* private fields */ }

A caster for trait-to-trait casting.

Given a trait object and the dyn Target type, first upcast it to dyn Any, then get the caster using the concrete type id fetched from the Any object, and the type id of the concrete caster Caster<dyn Target>. The just get the caster from the storage and do the cast.

The caster functions can be simply implemented by downcasting the Any object to the concrete type and then just let rust do the rest type checking.

Example

A caster can be implemented like this:

let caster = Caster::<dyn Target> {
    cast_ref: |any| any.downcast_ref::<Concrete>().unwrap() as &dyn Target,
    cast_mut: |any| any.downcast_mut::<Concrete>().unwrap() as &mut dyn Target,
}

Implementations

impl<T: ?Sized + 'static> Caster<T>

pub fn new( cast_ref: fn(_: &dyn Any) -> &T, cast_mut: fn(_: &mut dyn Any) -> &mut T ) -> Self

Create a new caster.