Auto merge of #8060 - nox:deref-js, r=Ms2ger

Implement Deref<Target=T> for JS<T> where T: Reflectable

We can only borrow `JS<T>` from rooted things, so it's safe to deref it.
The only types that provide mutable `JS<T>` things are `MutHeap<JS<T>>` and
`MutNullableHeap<JS<T>>`, which don't actually expose that they contain
`JS<T>` values.

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This commit is contained in:
bors-servo 2015-10-19 06:32:05 -06:00
commit 1a376aa75d
23 changed files with 187 additions and 274 deletions

View file

@ -96,6 +96,16 @@ impl<T: Reflectable> JS<T> {
}
}
impl<T: Reflectable> Deref for JS<T> {
type Target = T;
fn deref(&self) -> &T {
// We can only have &JS<T> from a rooted thing, so it's safe to deref
// it to &T.
unsafe { &**self.ptr }
}
}
impl<T: Reflectable> JSTraceable for JS<T> {
fn trace(&self, trc: *mut JSTracer) {
trace_reflector(trc, "", unsafe { (**self.ptr).reflector() });