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use super::*;
use core::marker::PhantomData;
/// `Weak` holds a non-owning reference to an object.
#[derive(Clone, PartialEq, Eq, Default)]
pub struct Weak<I: Interface>(Option<imp::IWeakReference>, PhantomData<I>);
impl<I: Interface> Weak<I> {
/// Creates a new `Weak` object without any backing object.
pub fn new() -> Self {
Self(None, PhantomData)
}
/// Attempts to upgrade the weak reference to a strong reference.
pub fn upgrade(&self) -> Option<I> {
self.0
.as_ref()
.and_then(|inner| unsafe { inner.Resolve().ok() })
}
pub(crate) fn downgrade(source: &imp::IWeakReferenceSource) -> Result<Self> {
let reference = unsafe { source.GetWeakReference().ok() };
Ok(Self(reference, PhantomData))
}
}
unsafe impl<I: Interface> Send for Weak<I> {}
unsafe impl<I: Interface> Sync for Weak<I> {}