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use core::any::{Any, AnyRefExt};
use core::clone::Clone;
use core::cmp::{PartialEq, PartialOrd, Eq, Ord, Ordering};
use core::default::Default;
use core::fmt;
use core::hash::{mod, Hash};
use core::kinds::Sized;
use core::mem;
use core::option::Option;
use core::ptr::Unique;
use core::raw::TraitObject;
use core::result::Result;
use core::result::Result::{Ok, Err};
use core::ops::{Deref, DerefMut};
#[lang = "exchange_heap"]
#[experimental = "may be renamed; uncertain about custom allocator design"]
pub static HEAP: () = ();
#[lang = "owned_box"]
#[unstable = "custom allocators will add an additional type parameter (with default)"]
pub struct Box<T>(Unique<T>);
#[stable]
impl<T: Default> Default for Box<T> {
#[stable]
fn default() -> Box<T> { box Default::default() }
}
#[stable]
impl<T> Default for Box<[T]> {
#[stable]
fn default() -> Box<[T]> { box [] }
}
#[stable]
impl<T: Clone> Clone for Box<T> {
#[inline]
fn clone(&self) -> Box<T> { box {(**self).clone()} }
#[inline]
fn clone_from(&mut self, source: &Box<T>) {
(**self).clone_from(&(**source));
}
}
#[stable]
impl<Sized? T: PartialEq> PartialEq for Box<T> {
#[inline]
fn eq(&self, other: &Box<T>) -> bool { PartialEq::eq(&**self, &**other) }
#[inline]
fn ne(&self, other: &Box<T>) -> bool { PartialEq::ne(&**self, &**other) }
}
#[stable]
impl<Sized? T: PartialOrd> PartialOrd for Box<T> {
#[inline]
fn partial_cmp(&self, other: &Box<T>) -> Option<Ordering> {
PartialOrd::partial_cmp(&**self, &**other)
}
#[inline]
fn lt(&self, other: &Box<T>) -> bool { PartialOrd::lt(&**self, &**other) }
#[inline]
fn le(&self, other: &Box<T>) -> bool { PartialOrd::le(&**self, &**other) }
#[inline]
fn ge(&self, other: &Box<T>) -> bool { PartialOrd::ge(&**self, &**other) }
#[inline]
fn gt(&self, other: &Box<T>) -> bool { PartialOrd::gt(&**self, &**other) }
}
#[stable]
impl<Sized? T: Ord> Ord for Box<T> {
#[inline]
fn cmp(&self, other: &Box<T>) -> Ordering {
Ord::cmp(&**self, &**other)
}
#[stable]}
impl<Sized? T: Eq> Eq for Box<T> {}
impl<S: hash::Writer, Sized? T: Hash<S>> Hash<S> for Box<T> {
#[inline]
fn hash(&self, state: &mut S) {
(**self).hash(state);
}
}
#[unstable = "post-DST and coherence changes, this will not be a trait but \
rather a direct `impl` on `Box<Any>`"]
pub trait BoxAny {
#[unstable = "naming conventions around accessing innards may change"]
fn downcast<T: 'static>(self) -> Result<Box<T>, Self>;
}
#[stable]
impl BoxAny for Box<Any> {
#[inline]
fn downcast<T: 'static>(self) -> Result<Box<T>, Box<Any>> {
if self.is::<T>() {
unsafe {
let to: TraitObject =
mem::transmute::<Box<Any>, TraitObject>(self);
Ok(mem::transmute(to.data))
}
} else {
Err(self)
}
}
}
impl<Sized? T: fmt::Show> fmt::Show for Box<T> {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
(**self).fmt(f)
}
}
impl fmt::Show for Box<Any+'static> {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
f.pad("Box<Any>")
}
}
impl<Sized? T> Deref<T> for Box<T> {
fn deref(&self) -> &T { &**self }
}
impl<Sized? T> DerefMut<T> for Box<T> {
fn deref_mut(&mut self) -> &mut T { &mut **self }
}
#[cfg(test)]
mod test {
#[test]
fn test_owned_clone() {
let a = box 5i;
let b: Box<int> = a.clone();
assert!(a == b);
}
#[test]
fn any_move() {
let a = box 8u as Box<Any>;
let b = box Test as Box<Any>;
match a.downcast::<uint>() {
Ok(a) => { assert!(a == box 8u); }
Err(..) => panic!()
}
match b.downcast::<Test>() {
Ok(a) => { assert!(a == box Test); }
Err(..) => panic!()
}
let a = box 8u as Box<Any>;
let b = box Test as Box<Any>;
assert!(a.downcast::<Box<Test>>().is_err());
assert!(b.downcast::<Box<uint>>().is_err());
}
#[test]
fn test_show() {
let a = box 8u as Box<Any>;
let b = box Test as Box<Any>;
let a_str = a.to_str();
let b_str = b.to_str();
assert_eq!(a_str, "Box<Any>");
assert_eq!(b_str, "Box<Any>");
let a = &8u as &Any;
let b = &Test as &Any;
let s = format!("{}", a);
assert_eq!(s, "&Any");
let s = format!("{}", b);
assert_eq!(s, "&Any");
}
#[test]
fn deref() {
fn homura<T: Deref<i32>>(_: T) { }
homura(box 765i32);
}
}