1 files changed, 101 insertions, 0 deletions
diff --git a/src/libstd/owned.rs b/src/libstd/owned.rs
new file mode 100644
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+++ b/src/libstd/owned.rs
@@ -0,0 +1,101 @@
+// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+//! Operations on unique pointer types
+
+use any::{Any, AnyRefExt};
+use clone::Clone;
+use cmp::{Eq, Ord, TotalEq, TotalOrd, Ordering};
+use default::Default;
+use intrinsics;
+use mem;
+use raw::TraitObject;
+use result::{Ok, Err, Result};
+
+/// A value that represents the global exchange heap. This is the default
+/// place that the `box` keyword allocates into when no place is supplied.
+///
+/// The following two examples are equivalent:
+///
+///     let foo = box(HEAP) Bar::new(...);
+///     let foo = box Bar::new(...);
+#[lang="exchange_heap"]
+pub static HEAP: () = ();
+
+/// A type that represents a uniquely-owned value.
+#[lang="owned_box"]
+pub struct Box<T>(*T);
+
+impl<T: Default> Default for Box<T> {
+    fn default() -> Box<T> { box Default::default() }
+}
+
+impl<T: Clone> Clone for Box<T> {
+    /// Return a copy of the owned box.
+    #[inline]
+    fn clone(&self) -> Box<T> { box {(**self).clone()} }
+
+    /// Perform copy-assignment from `source` by reusing the existing allocation.
+    #[inline]
+    fn clone_from(&mut self, source: &Box<T>) {
+        (**self).clone_from(&(**source));
+    }
+}
+
+// box pointers
+impl<T:Eq> Eq for Box<T> {
+    #[inline]
+    fn eq(&self, other: &Box<T>) -> bool { *(*self) == *(*other) }
+    #[inline]
+    fn ne(&self, other: &Box<T>) -> bool { *(*self) != *(*other) }
+}
+impl<T:Ord> Ord for Box<T> {
+    #[inline]
+    fn lt(&self, other: &Box<T>) -> bool { *(*self) < *(*other) }
+    #[inline]
+    fn le(&self, other: &Box<T>) -> bool { *(*self) <= *(*other) }
+    #[inline]
+    fn ge(&self, other: &Box<T>) -> bool { *(*self) >= *(*other) }
+    #[inline]
+    fn gt(&self, other: &Box<T>) -> bool { *(*self) > *(*other) }
+}
+impl<T: TotalOrd> TotalOrd for Box<T> {
+    #[inline]
+    fn cmp(&self, other: &Box<T>) -> Ordering { (**self).cmp(*other) }
+}
+impl<T: TotalEq> TotalEq for Box<T> {}
+
+/// Extension methods for an owning `Any` trait object
+pub trait AnyOwnExt {
+    /// Returns the boxed value if it is of type `T`, or
+    /// `Err(Self)` if it isn't.
+    fn move<T: 'static>(self) -> Result<Box<T>, Self>;
+}
+
+impl AnyOwnExt for Box<Any> {
+    #[inline]
+    fn move<T: 'static>(self) -> Result<Box<T>, Box<Any>> {
+        if self.is::<T>() {
+            unsafe {
+                // Get the raw representation of the trait object
+                let to: TraitObject =
+                    *mem::transmute::<&Box<Any>, &TraitObject>(&self);
+
+                // Prevent destructor on self being run
+                intrinsics::forget(self);
+
+                // Extract the data pointer
+                Ok(mem::transmute(to.data))
+            }
+        } else {
+            Err(self)
+        }
+    }
+}