diff options
| -rw-r--r-- | src/libcore/clone.rs | 47 |
1 files changed, 36 insertions, 11 deletions
diff --git a/src/libcore/clone.rs b/src/libcore/clone.rs index 2ff860916c5..9c1c83b47ca 100644 --- a/src/libcore/clone.rs +++ b/src/libcore/clone.rs @@ -22,6 +22,8 @@ by convention implementing the `Clone` trait and calling the */ +use core::kinds::Const; + pub trait Clone { /// Return a deep copy of the owned object tree. Types with shared ownership like managed boxes /// are cloned with a shallow copy. @@ -78,11 +80,32 @@ clone_impl!(char) pub trait DeepClone { /// Return a deep copy of the object tree. Types with shared ownership are also copied via a - /// deep copy, unlike `Clone`. Note that this is currently unimplemented for managed boxes, as - /// it would need to handle cycles. + /// deep copy, unlike `Clone`. fn deep_clone(&self) -> Self; } +impl<T: DeepClone> DeepClone for ~T { + /// Return a deep copy of the owned box. + #[inline(always)] + fn deep_clone(&self) -> ~T { ~(**self).deep_clone() } +} + +// FIXME: #6525: should also be implemented for `T: Owned + DeepClone` +impl<T: Const + DeepClone> DeepClone for @T { + /// Return a deep copy of the managed box. The `Const` trait is required to prevent performing + /// a deep clone of a potentially cyclical type. + #[inline(always)] + fn deep_clone(&self) -> @T { @(**self).deep_clone() } +} + +// FIXME: #6525: should also be implemented for `T: Owned + DeepClone` +impl<T: Const + DeepClone> DeepClone for @mut T { + /// Return a deep copy of the managed box. The `Const` trait is required to prevent performing + /// a deep clone of a potentially cyclical type. + #[inline(always)] + fn deep_clone(&self) -> @mut T { @mut (**self).deep_clone() } +} + macro_rules! deep_clone_impl( ($t:ty) => { impl DeepClone for $t { @@ -93,12 +116,6 @@ macro_rules! deep_clone_impl( } ) -impl<T: DeepClone> DeepClone for ~T { - /// Return a deep copy of the owned box. - #[inline(always)] - fn deep_clone(&self) -> ~T { ~(**self).deep_clone() } -} - deep_clone_impl!(int) deep_clone_impl!(i8) deep_clone_impl!(i16) @@ -121,21 +138,29 @@ deep_clone_impl!(char) #[test] fn test_owned_clone() { - let a: ~int = ~5i; + let a = ~5i; let b: ~int = a.clone(); assert!(a == b); } #[test] fn test_managed_clone() { - let a: @int = @5i; + let a = @5i; let b: @int = a.clone(); assert!(a == b); } #[test] +fn test_managed_mut_deep_clone() { + let x = @mut 5i; + let y: @mut int = x.deep_clone(); + *x = 20; + assert_eq!(*y, 5); +} + +#[test] fn test_managed_mut_clone() { - let a: @mut int = @mut 5i; + let a = @mut 5i; let b: @mut int = a.clone(); assert!(a == b); *b = 10; |