Go to Rust: just implbox

implbox.rs

use std::any::TypeId;
use std::marker::PhantomData;

unsafe impl<T: Send> Send for ImplBox<T> {}
unsafe impl<T: Sync> Sync for ImplBox<T> {}
pub struct ImplBox<T> {
    id: TypeId,
    ptr: *const (),
    destroy: fn(*const ()),
    _t: PhantomData<T>,
}
impl<T> ImplBox<T> {
    pub fn new(id: TypeId, destroy: fn(*const ()), ptr: *const ()) -> Self {
        Self {
            id,
            ptr,
            destroy,
            _t: Default::default(),
        }
    }

    pub fn with<F, Ret>(&self, id: TypeId, f: F) -> Ret
    where
        F: FnOnce(*const ()) -> Ret,
    {
        if self.id == id {
            f(self.ptr)
        } else {
            panic!("id mismatch");
        }
    }
}
impl<T> Drop for ImplBox<T> {
    fn drop(&mut self) {
        (self.destroy)(self.ptr);
    }
}