Forward Show, Eq, and Hash to RefCell's contents

src/libcollections/hash/mod.rs

@@ -67,6 +67,7 @@ use core::prelude::*;
 
 use alloc::boxed::Box;
 use alloc::rc::Rc;
+use core::cell::RefCell;
 use core::intrinsics::TypeId;
 use core::mem;
 
@@ -239,6 +240,13 @@ impl<S: Writer, T: Hash<S>> Hash<S> for Rc<T> {
     }
 }
 
+impl<S: Writer, T: Hash<S>> Hash<S> for RefCell<T> {
+    #[inline]
+    fn hash(&self, state: &mut S) {
+        self.borrow().hash(state);
+    }
+}
+
 impl<S: Writer, T: Hash<S>> Hash<S> for Option<T> {
     #[inline]
     fn hash(&self, state: &mut S) {

src/libcore/cell.rs

@@ -156,10 +156,11 @@
 // FIXME: Relationship to Atomic types and RWLock
 
 use clone::Clone;
-use cmp::PartialEq;
+use cmp::{PartialEq, Eq};
 use kinds::{marker, Copy};
 use ops::{Deref, DerefMut, Drop};
 use option::{None, Option, Some};
+use std::fmt;
 
 /// A mutable memory location that admits only `Copy` data.
 #[unstable = "likely to be renamed; otherwise stable"]
@@ -322,6 +323,16 @@ impl<T: PartialEq> PartialEq for RefCell<T> {
     }
 }
 
+#[unstable = "waiting for `Eq` to become stable"]
+impl<T: Eq> Eq for RefCell<T> {}
+
+#[unstable = "waiting for `Show` to become stable"]
+impl<T: fmt::Show> fmt::Show for RefCell<T> {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        self.borrow().fmt(f)
+    }
+}
+
 /// Wraps a borrowed reference to a value in a `RefCell` box.
 #[unstable]
 pub struct Ref<'b, T> {