Trait std::clone::Clone 1.0.0[−][src]
#[lang = "clone"]pub trait Clone {#[must_use = "cloning is often expensive and is not expected to have side effects"]fn clone(&self) -> Self; fn clone_from(&mut self, source: &Self) { ... } }
A common trait for the ability to explicitly duplicate an object.
Differs from Copy in that Copy is implicit and extremely inexpensive, while
Clone is always explicit and may or may not be expensive. In order to enforce
these characteristics, Rust does not allow you to reimplement Copy, but you
may reimplement Clone and run arbitrary code.
Since Clone is more general than Copy, you can automatically make anything
Copy be Clone as well.
Derivable
This trait can be used with #[derive] if all fields are Clone. The derived
implementation of clone calls clone on each field.
How can I implement Clone?
Types that are Copy should have a trivial implementation of Clone. More formally:
if T: Copy, x: T, and y: &T, then let x = y.clone(); is equivalent to let x = *y;.
Manual implementations should be careful to uphold this invariant; however, unsafe code
must not rely on it to ensure memory safety.
An example is an array holding more than 32 elements of a type that is Clone; the standard
library only implements Clone up until arrays of size 32. In this case, the implementation of
Clone cannot be derived, but can be implemented as:
#[derive(Copy)] struct Stats { frequencies: [i32; 100], } impl Clone for Stats { fn clone(&self) -> Stats { *self } }Run
Additional implementors
In addition to the implementors listed below,
the following types also implement Clone:
- Function item types (i.e. the distinct types defined for each function)
- Function pointer types (e.g.
fn() -> i32) - Array types, for all sizes, if the item type also implements
Clone(e.g.[i32; 123456]) - Tuple types, if each component also implements
Clone(e.g.(),(i32, bool)) - Closure types, if they capture no value from the environment
or if all such captured values implement
Clonethemselves. Note that variables captured by shared reference always implementClone(even if the referent doesn't), while variables captured by mutable reference never implementClone.
Required Methods
#[must_use = "cloning is often expensive and is not expected to have side effects"]
fn clone(&self) -> Self
Provided Methods
fn clone_from(&mut self, source: &Self)
Performs copy-assignment from source.
a.clone_from(&b) is equivalent to a = b.clone() in functionality,
but can be overridden to reuse the resources of a to avoid unnecessary
allocations.
Implementations on Foreign Types
impl Clone for TryFromSliceError[src]
impl Clone for TryFromSliceErrorfn clone(&self) -> TryFromSliceError[src]
fn clone(&self) -> TryFromSliceErrorfn clone_from(&mut self, source: &Self)1.0.0[src]
fn clone_from(&mut self, source: &Self)Implementors
impl Clone for i8x64impl<I, St, F> Clone for Scan<I, St, F> where
F: Clone,
I: Clone,
St: Clone,impl<'a, T> Clone for std::result::Iter<'a, T>impl Clone for LocalWakerimpl Clone for u8x2impl<I, P> Clone for SkipWhile<I, P> where
I: Clone,
P: Clone,impl<T> Clone for Once<T> where
T: Clone,impl Clone for ToLowercaseimpl Clone for CollectionAllocErrimpl Clone for m16x4impl Clone for NonZeroU8impl Clone for u8impl<I, P> Clone for TakeWhile<I, P> where
I: Clone,
P: Clone,impl<I> Clone for StepBy<I> where
I: Clone,impl Clone for NonZeroU32impl<I> Clone for Peekable<I> where
I: Clone + Iterator,
<I as Iterator>::Item: Clone,impl Clone for i64x8impl Clone for i128impl Clone for f64impl<T> Clone for *const T where
T: ?Sized,impl Clone for i32x4impl Clone for u8x32impl Clone for RangeFullimpl<I, U, F> Clone for FlatMap<I, U, F> where
F: Clone,
I: Clone,
U: Clone + IntoIterator,
<U as IntoIterator>::IntoIter: Clone,impl Clone for m1x32impl Clone for u8x4impl Clone for Pinnedimpl Clone for u16impl Clone for LayoutErrimpl<'a, P> Clone for RSplitTerminator<'a, P> where
P: Pattern<'a>,
<P as Pattern<'a>>::Searcher: Clone,impl Clone for m32x8impl Clone for EscapeDefaultimpl<A, B> Clone for Zip<A, B> where
A: Clone,
B: Clone,impl<I, U> Clone for Flatten<I> where
I: Iterator + Clone,
U: Iterator + Clone,
<I as Iterator>::Item: IntoIterator,
<<I as Iterator>::Item as IntoIterator>::IntoIter == U,
<<I as Iterator>::Item as IntoIterator>::Item == <U as Iterator>::Item,impl<T> Clone for Option<T> where
T: Clone,impl Clone for EscapeUnicodeimpl Clone for Layoutimpl Clone for u32x8impl Clone for DecodeUtf16Errorimpl<'a, P> Clone for std::str::RSplit<'a, P> where
P: Pattern<'a>,
<P as Pattern<'a>>::Searcher: Clone,impl<T> Clone for RefCell<T> where
T: Clone,impl Clone for m1x64impl<I> Clone for Take<I> where
I: Clone,impl Clone for i16x32impl<'a, T> Clone for &'a T where
T: ?Sized,impl<'a> Clone for LinesAny<'a>impl Clone for Wakerimpl<'a, T> Clone for Chunks<'a, T>impl Clone for SearchStepimpl<'a, T, P> Clone for std::slice::RSplit<'a, T, P> where
P: Clone + FnMut(&T) -> bool,
T: 'a + Clone,impl<I, F> Clone for FilterMap<I, F> where
F: Clone,
I: Clone,impl Clone for f32x8impl Clone for u16x4impl Clone for ParseBoolErrorimpl Clone for f64x8impl Clone for std::sync::atomic::Orderingimpl Clone for i8x4impl<'a, 'b> Clone for CharSliceSearcher<'a, 'b>impl<A, B> Clone for Chain<A, B> where
A: Clone,
B: Clone,impl Clone for FpCategoryimpl Clone for ToUppercaseimpl Clone for TypeIdimpl Clone for m8x32impl<H> Clone for BuildHasherDefault<H>impl<I> Clone for Fuse<I> where
I: Clone,impl Clone for m1x8impl Clone for boolimpl Clone for i16x2impl<'a> Clone for CharSearcher<'a>impl Clone for TraitObjectimpl Clone for i32impl<'a> Clone for Chars<'a>impl Clone for i16impl Clone for f32x2impl Clone for i64x2impl<'a, P> Clone for Matches<'a, P> where
P: Pattern<'a>,
<P as Pattern<'a>>::Searcher: Clone,impl<T> Clone for NonNull<T> where
T: ?Sized,impl Clone for i32x16impl Clone for u32x16impl<I> Clone for DecodeUtf8<I> where
I: Clone + Iterator<Item = u8>,impl Clone for NonZeroUsizeimpl Clone for NoneErrorimpl<'a> Clone for Bytes<'a>impl<I, P> Clone for Filter<I, P> where
I: Clone,
P: Clone,impl Clone for i32x8impl Clone for f32impl Clone for NonZeroU64impl<Idx> Clone for RangeTo<Idx> where
Idx: Clone,impl<'a, F> Clone for CharPredicateSearcher<'a, F> where
F: Clone + FnMut(char) -> bool,impl Clone for m16x8impl Clone for ParseCharErrorimpl Clone for m16x2impl Clone for u16x16impl Clone for NonZeroU16impl<Y, R> Clone for GeneratorState<Y, R> where
R: Clone,
Y: Clone,impl Clone for m8x4impl<T> Clone for *mut T where
T: ?Sized,impl<T> Clone for Bound<T> where
T: Clone,impl<'a, P> Clone for SplitTerminator<'a, P> where
P: Pattern<'a>,
<P as Pattern<'a>>::Searcher: Clone,impl Clone for m16x16impl<'a, P> Clone for RMatchIndices<'a, P> where
P: Pattern<'a>,
<P as Pattern<'a>>::Searcher: Clone,impl<A> Clone for Repeat<A> where
A: Clone,impl Clone for f32x16impl Clone for m64x2impl Clone for f32x4impl Clone for ParseIntErrorimpl<T> Clone for Wrapping<T> where
T: Clone,impl Clone for u16x32impl Clone for usizeimpl<'a> Clone for CharIndices<'a>impl<Idx> Clone for RangeInclusive<Idx> where
Idx: Clone,impl Clone for i8x8impl<'a> Clone for EncodeUtf16<'a>impl Clone for i64x4impl Clone for AllocErrimpl Clone for i16x4impl<Idx> Clone for std::ops::Range<Idx> where
Idx: Clone,impl Clone for i64impl<I> Clone for Enumerate<I> where
I: Clone,impl<T> Clone for Cell<T> where
T: Copy,impl<T> Clone for Empty<T>impl Clone for std::cmp::Orderingimpl<F> Clone for RepeatWith<F> where
F: Clone,impl<T> Clone for Rev<T> where
T: Clone,impl<T> Clone for Reverse<T> where
T: Clone,impl Clone for i8x2impl Clone for u128impl<I, F> Clone for Inspect<I, F> where
F: Clone,
I: Clone,impl<T, E> Clone for Result<T, E> where
E: Clone,
T: Clone,impl Clone for u16x2impl<I> Clone for Cycle<I> where
I: Clone,impl Clone for u16x8impl<T> Clone for Discriminant<T>impl Clone for i16x16impl Clone for u8x16impl<'a> Clone for SplitWhitespace<'a>impl<'a, T, P> Clone for std::slice::Split<'a, T, P> where
P: Clone + FnMut(&T) -> bool,impl<'a, A> Clone for std::option::Iter<'a, A>impl<'a, 'b> Clone for StrSearcher<'a, 'b>impl Clone for u8x8impl Clone for SipHasherimpl Clone for m8x16impl Clone for NonZeroU128impl<'a, P> Clone for std::str::Split<'a, P> where
P: Pattern<'a>,
<P as Pattern<'a>>::Searcher: Clone,impl<T> Clone for std::result::IntoIter<T> where
T: Clone,impl<I> Clone for Cloned<I> where
I: Clone,impl Clone for ParseFloatErrorimpl Clone for Utf8Errorimpl Clone for charimpl Clone for isizeimpl Clone for f64x4impl Clone for Durationimpl Clone for u64impl Clone for u32impl Clone for u32x2impl Clone for u32x4impl Clone for UnicodeVersionimpl<T> Clone for PhantomData<T> where
T: ?Sized,impl<'a, P> Clone for RSplitN<'a, P> where
P: Pattern<'a>,
<P as Pattern<'a>>::Searcher: Clone,impl Clone for !impl<I> Clone for Skip<I> where
I: Clone,impl Clone for m32x2impl Clone for m8x2impl<T> Clone for ManuallyDrop<T> where
T: Clone,impl Clone for u64x2impl Clone for m64x4impl<'a, P> Clone for RMatches<'a, P> where
P: Pattern<'a>,
<P as Pattern<'a>>::Searcher: Clone,impl Clone for f64x2impl Clone for CannotReallocInPlaceimpl Clone for u64x4impl Clone for CharTryFromErrorimpl Clone for Errorimpl Clone for i32x2impl Clone for i16x8impl<A> Clone for std::option::IntoIter<A> where
A: Clone,impl Clone for i8x32impl<I> Clone for DecodeUtf16<I> where
I: Clone + Iterator<Item = u16>,impl<'a> Clone for Lines<'a>impl Clone for m32x4impl<'a, P> Clone for SplitN<'a, P> where
P: Pattern<'a>,
<P as Pattern<'a>>::Searcher: Clone,impl Clone for EscapeDebugimpl Clone for u64x8impl<I, F> Clone for Map<I, F> where
F: Clone,
I: Clone,impl Clone for u8x64impl Clone for i8impl<Idx> Clone for RangeFrom<Idx> where
Idx: Clone,impl<'a, T> Clone for Windows<'a, T>impl<'a, T> Clone for std::slice::Iter<'a, T>impl Clone for m8x8impl<'a, T> Clone for ExactChunks<'a, T>impl Clone for i8x16impl<T> Clone for Poll<T> where
T: Clone,impl<'a> Clone for Arguments<'a>impl<'a, P> Clone for MatchIndices<'a, P> where
P: Pattern<'a>,
<P as Pattern<'a>>::Searcher: Clone,impl<Idx> Clone for RangeToInclusive<Idx> where
Idx: Clone,impl Clone for m1x16impl Clone for TryFromIntErrorimpl<T> Clone for LinkedList<T> where
T: Clone,impl<T> Clone for std::vec::IntoIter<T> where
T: Clone,impl<'a, K, V> Clone for std::collections::btree_map::Iter<'a, K, V>impl<'a, T> Clone for std::collections::vec_deque::Iter<'a, T>impl Clone for Box<str>impl<'a, T> Clone for std::collections::btree_set::Iter<'a, T>impl Clone for Globalimpl<T> Clone for std::rc::Weak<T> where
T: ?Sized,impl<T> Clone for std::collections::linked_list::IntoIter<T> where
T: Clone,impl<T> Clone for VecDeque<T> where
T: Clone,impl<'a, T> Clone for std::collections::linked_list::Iter<'a, T>impl<K, V> Clone for BTreeMap<K, V> where
K: Clone,
V: Clone,impl<'a, T> Clone for std::collections::binary_heap::Iter<'a, T>impl<'a, T> Clone for std::collections::btree_set::Range<'a, T>impl<T> Clone for std::collections::vec_deque::IntoIter<T> where
T: Clone,impl<T> Clone for std::collections::binary_heap::IntoIter<T> where
T: Clone,impl<'a, T> Clone for std::collections::btree_set::SymmetricDifference<'a, T>impl<'a, K, V> Clone for std::collections::btree_map::Keys<'a, K, V>impl<T> Clone for Box<T> where
T: Clone,impl<T> Clone for BTreeSet<T> where
T: Clone,impl<T> Clone for Box<[T]> where
T: Clone,impl<T> Clone for std::sync::Weak<T> where
T: ?Sized,impl<'a, B> Clone for Cow<'a, B> where
B: ToOwned + ?Sized,impl Clone for Stringimpl<T> Clone for Rc<T> where
T: ?Sized,impl<'a, K, V> Clone for std::collections::btree_map::Range<'a, K, V>impl<'a, T> Clone for std::collections::btree_set::Intersection<'a, T>impl<'a, T> Clone for std::collections::btree_set::Union<'a, T>impl<T> Clone for Arc<T> where
T: ?Sized,impl Clone for ParseErrorimpl<'a, K, V> Clone for std::collections::btree_map::Values<'a, K, V>impl<T> Clone for BinaryHeap<T> where
T: Clone,impl<T> Clone for Vec<T> where
T: Clone,impl<'a, T> Clone for std::collections::btree_set::Difference<'a, T>impl Clone for ThreadIdimpl Clone for Threadimpl<K: Clone, V: Clone, S: Clone> Clone for HashMap<K, V, S>impl<'a, K, V> Clone for std::collections::hash_map::Iter<'a, K, V>impl<'a, K, V> Clone for std::collections::hash_map::Keys<'a, K, V>impl<'a, K, V> Clone for std::collections::hash_map::Values<'a, K, V>impl Clone for RandomStateimpl Clone for DefaultHasherimpl<T: Clone, S: Clone> Clone for HashSet<T, S>impl<'a, K> Clone for std::collections::hash_set::Iter<'a, K>impl<'a, T, S> Clone for std::collections::hash_set::Intersection<'a, T, S>impl<'a, T, S> Clone for std::collections::hash_set::Difference<'a, T, S>impl<'a, T, S> Clone for std::collections::hash_set::SymmetricDifference<'a, T, S>impl<'a, T, S> Clone for std::collections::hash_set::Union<'a, T, S>impl Clone for VarErrorimpl Clone for CStringimpl Clone for NulErrorimpl Clone for FromBytesWithNulErrorimpl Clone for IntoStringErrorimpl Clone for OsStringimpl Clone for Metadataimpl Clone for OpenOptionsimpl Clone for Permissionsimpl Clone for FileTypeimpl<T: Clone> Clone for Cursor<T>impl Clone for ErrorKindimpl Clone for SeekFromimpl Clone for IpAddrimpl Clone for Ipv6MulticastScopeimpl Clone for Ipv4Addrimpl Clone for Ipv6Addrimpl Clone for std::net::SocketAddrimpl Clone for SocketAddrV4impl Clone for SocketAddrV6impl Clone for AddrParseErrorimpl Clone for Shutdownimpl Clone for statimpl<'a> Clone for Prefix<'a>impl<'a> Clone for PrefixComponent<'a>impl<'a> Clone for Component<'a>impl<'a> Clone for Components<'a>impl<'a> Clone for std::path::Iter<'a>impl<'a> Clone for Ancestors<'a>impl Clone for PathBufimpl Clone for StripPrefixErrorimpl Clone for Outputimpl Clone for ExitStatusimpl Clone for ExitCodeimpl<T: Clone> Clone for SendError<T>impl Clone for RecvErrorimpl Clone for TryRecvErrorimpl Clone for RecvTimeoutErrorimpl<T: Clone> Clone for TrySendError<T>impl<T> Clone for Sender<T>impl<T> Clone for SyncSender<T>impl Clone for WaitTimeoutResultimpl Clone for Instantimpl Clone for SystemTimeimpl Clone for SystemTimeErrorimpl<'a> Clone for EncodeWide<'a>impl Clone for std::os::unix::net::SocketAddr