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pub use crate::dom::bindings::codegen::InheritTypes::*;
use crate::dom::bindings::conversions::get_dom_class;
use crate::dom::bindings::conversions::{DerivedFrom, IDLInterface};
use crate::dom::bindings::reflector::DomObject;
use std::mem;
pub trait Castable: IDLInterface + DomObject + Sized {
fn is<T>(&self) -> bool
where
T: DerivedFrom<Self>,
{
let class = unsafe { get_dom_class(self.reflector().get_jsobject().get()).unwrap() };
T::derives(class)
}
fn upcast<T>(&self) -> &T
where
T: Castable,
Self: DerivedFrom<T>,
{
unsafe { mem::transmute(self) }
}
fn downcast<T>(&self) -> Option<&T>
where
T: DerivedFrom<Self>,
{
if self.is::<T>() {
Some(unsafe { mem::transmute(self) })
} else {
None
}
}
}
pub trait HasParent {
type Parent;
fn as_parent(&self) -> &Self::Parent;
}