pub trait Clone {
fn clone(&self) -> Self;
fn clone_from(&mut self, source: &Self) { ... }
}Expand description
A common trait for the ability to explicitly duplicate an object.
Differs from Copy in that Copy is implicit and an inexpensive bit-wise copy, 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.
For a generic struct, #[derive] implements Clone conditionally by adding bound Clone on
generic parameters.
// `derive` implements Clone for Reading<T> when T is Clone.
#[derive(Clone)]
struct Reading<T> {
frequency: T,
}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 a generic struct holding a function pointer. In this case, the
implementation of Clone cannot be derived, but can be implemented as:
struct Generate<T>(fn() -> T);
impl<T> Copy for Generate<T> {}
impl<T> Clone for Generate<T> {
fn clone(&self) -> Self {
*self
}
}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) - 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
Provided Methods
fn clone_from(&mut self, source: &Self)
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.
Implementors
impl Clone for std::cmp::Ordering
impl Clone for TryReserveErrorKind
impl Clone for Infallible
impl Clone for VarError
impl Clone for Alignment
impl Clone for ErrorKind
impl Clone for SeekFrom
impl Clone for IpAddr
impl Clone for Ipv6MulticastScope
impl Clone for Shutdown
impl Clone for std::net::SocketAddr
impl Clone for FpCategory
impl Clone for IntErrorKind
impl Clone for BacktraceStyle
impl Clone for Which
impl Clone for SearchStep
impl Clone for std::sync::atomic::Ordering
impl Clone for RecvTimeoutError
impl Clone for TryRecvError
impl Clone for bool
impl Clone for char
impl Clone for f32
impl Clone for f64
impl Clone for i8
impl Clone for i16
impl Clone for i32
impl Clone for i64
impl Clone for i128
impl Clone for isize
impl Clone for !
impl Clone for u8
impl Clone for u16
impl Clone for u32
impl Clone for u64
impl Clone for u128
impl Clone for ()
impl Clone for usize
impl Clone for CpuidResult
impl Clone for __m128
impl Clone for __m128bh
impl Clone for __m128d
impl Clone for __m128i
impl Clone for __m256
impl Clone for __m256bh
impl Clone for __m256d
impl Clone for __m256i
impl Clone for __m512
impl Clone for __m512bh
impl Clone for __m512d
impl Clone for __m512i
impl Clone for FromBytesUntilNulError
impl Clone for AllocError
impl Clone for Global
impl Clone for Layout
impl Clone for LayoutError
impl Clone for System
impl Clone for TypeId
impl Clone for TryFromSliceError
impl Clone for std::ascii::EscapeDefault
impl Clone for Box<str, Global>
impl Clone for Box<CStr, Global>
impl Clone for Box<OsStr>
impl Clone for Box<Path>
impl Clone for CharTryFromError
impl Clone for DecodeUtf16Error
impl Clone for std::char::EscapeDebug
impl Clone for std::char::EscapeDefault
impl Clone for std::char::EscapeUnicode
impl Clone for ParseCharError
impl Clone for ToLowercase
impl Clone for ToUppercase
impl Clone for TryFromCharError
impl Clone for DefaultHasher
impl Clone for RandomState
impl Clone for TryReserveError
impl Clone for CString
impl Clone for FromBytesWithNulError
impl Clone for FromVecWithNulError
impl Clone for IntoStringError
impl Clone for NulError
impl Clone for OsString
impl Clone for Error
impl Clone for FileTimes
impl Clone for FileType
impl Clone for Metadata
impl Clone for OpenOptions
impl Clone for Permissions
impl Clone for SipHasher
impl Clone for std::io::Empty
impl Clone for Sink
impl Clone for PhantomPinned
impl Clone for Assume
impl Clone for AddrParseError
impl Clone for Ipv4Addr
impl Clone for Ipv6Addr
impl Clone for SocketAddrV4
impl Clone for SocketAddrV6
impl Clone for NonZeroI8
impl Clone for NonZeroI16
impl Clone for NonZeroI32
impl Clone for NonZeroI64
impl Clone for NonZeroI128
impl Clone for NonZeroIsize
impl Clone for NonZeroU8
impl Clone for NonZeroU16
impl Clone for NonZeroU32
impl Clone for NonZeroU64
impl Clone for NonZeroU128
impl Clone for NonZeroUsize
impl Clone for ParseFloatError
impl Clone for ParseIntError
impl Clone for TryFromIntError
impl Clone for RangeFull
impl Clone for stat
Available on Linux only.
impl Clone for std::os::unix::net::SocketAddr
Available on Unix only.
impl Clone for SocketCred
Available on (Android or Linux) and Unix only.
impl Clone for UCred
Available on Unix only.
impl Clone for InvalidHandleError
Available on Windows only.
impl Clone for NullHandleError
Available on Windows only.
impl Clone for PathBuf
impl Clone for StripPrefixError
impl Clone for ExitCode
impl Clone for ExitStatus
impl Clone for ExitStatusError
impl Clone for Output
impl Clone for ParseBoolError
impl Clone for Utf8Error
impl Clone for FromUtf8Error
impl Clone for String
impl Clone for RecvError
impl Clone for WaitTimeoutResult
impl Clone for RawWakerVTable
impl Clone for Waker
impl Clone for AccessError
impl Clone for Thread
impl Clone for ThreadId
impl Clone for Duration
impl Clone for FromFloatSecsError
impl Clone for Instant
impl Clone for SystemTime
impl Clone for SystemTimeError
impl<'a> Clone for Component<'a>
impl<'a> Clone for Prefix<'a>
impl<'a> Clone for std::error::Chain<'a>
impl<'a> Clone for Arguments<'a>
impl<'a> Clone for IoSlice<'a>
impl<'a> Clone for EncodeWide<'a>
impl<'a> Clone for Location<'a>
impl<'a> Clone for Ancestors<'a>
impl<'a> Clone for Components<'a>
impl<'a> Clone for std::path::Iter<'a>
impl<'a> Clone for PrefixComponent<'a>
impl<'a> Clone for EscapeAscii<'a>
impl<'a> Clone for CharSearcher<'a>
impl<'a> Clone for Bytes<'a>
impl<'a> Clone for CharIndices<'a>
impl<'a> Clone for Chars<'a>
impl<'a> Clone for EncodeUtf16<'a>
impl<'a> Clone for std::str::EscapeDebug<'a>
impl<'a> Clone for std::str::EscapeDefault<'a>
impl<'a> Clone for std::str::EscapeUnicode<'a>
impl<'a> Clone for Lines<'a>
impl<'a> Clone for LinesAny<'a>
impl<'a> Clone for SplitAsciiWhitespace<'a>
impl<'a> Clone for SplitWhitespace<'a>
impl<'a, 'b> Clone for CharSliceSearcher<'a, 'b>
impl<'a, 'b> Clone for StrSearcher<'a, 'b>
impl<'a, 'b, const N: usize> Clone for CharArrayRefSearcher<'a, 'b, N>
impl<'a, F> Clone for CharPredicateSearcher<'a, F> where
F: Clone + FnMut(char) -> bool,
impl<'a, P> Clone for MatchIndices<'a, P> where
P: Pattern<'a>,
<P as Pattern<'a>>::Searcher: Clone,
impl<'a, P> Clone for Matches<'a, P> where
P: Pattern<'a>,
<P as Pattern<'a>>::Searcher: Clone,
impl<'a, P> Clone for RMatchIndices<'a, P> where
P: Pattern<'a>,
<P as Pattern<'a>>::Searcher: Clone,
impl<'a, P> Clone for RMatches<'a, P> where
P: Pattern<'a>,
<P as Pattern<'a>>::Searcher: Clone,
impl<'a, P> Clone for std::str::RSplit<'a, P> where
P: Pattern<'a>,
<P as Pattern<'a>>::Searcher: Clone,
impl<'a, P> Clone for RSplitN<'a, P> where
P: Pattern<'a>,
<P as Pattern<'a>>::Searcher: Clone,
impl<'a, P> Clone for RSplitTerminator<'a, P> where
P: Pattern<'a>,
<P as Pattern<'a>>::Searcher: Clone,
impl<'a, P> Clone for std::str::Split<'a, P> where
P: Pattern<'a>,
<P as Pattern<'a>>::Searcher: Clone,
impl<'a, P> Clone for std::str::SplitInclusive<'a, P> where
P: Pattern<'a>,
<P as Pattern<'a>>::Searcher: Clone,
impl<'a, P> Clone for SplitN<'a, P> where
P: Pattern<'a>,
<P as Pattern<'a>>::Searcher: Clone,
impl<'a, P> Clone for SplitTerminator<'a, P> where
P: Pattern<'a>,
<P as Pattern<'a>>::Searcher: Clone,
impl<'a, T> Clone for RChunksExact<'a, T>
impl<'a, T, const N: usize> Clone for ArrayWindows<'a, T, N> where
T: 'a + Clone,
impl<'a, const N: usize> Clone for CharArraySearcher<'a, N>
impl<'f> Clone for VaListImpl<'f>
impl<'fd> Clone for BorrowedFd<'fd>
impl<'handle> Clone for BorrowedHandle<'handle>
Available on Windows only.
impl<'socket> Clone for BorrowedSocket<'socket>
Available on Windows only.
impl<A> Clone for Repeat<A> where
A: Clone,
impl<A> Clone for std::option::IntoIter<A> where
A: Clone,
impl<A> Clone for std::option::Iter<'_, A>
impl<A, B> Clone for std::iter::Chain<A, B> where
A: Clone,
B: Clone,
impl<A, B> Clone for Zip<A, B> where
A: Clone,
B: Clone,
impl<B> Clone for Cow<'_, B> where
B: ToOwned + ?Sized,
impl<B, C> Clone for ControlFlow<B, C> where
B: Clone,
C: Clone,
impl<Dyn> Clone for DynMetadata<Dyn> where
Dyn: ?Sized,
impl<F> Clone for FromFn<F> where
F: Clone,
impl<F> Clone for OnceWith<F> where
F: Clone,
impl<F> Clone for RepeatWith<F> where
F: Clone,
impl<H> Clone for BuildHasherDefault<H>
impl<I> Clone for FromIter<I> where
I: Clone,
impl<I> Clone for DecodeUtf16<I> where
I: Clone + Iterator<Item = u16>,
impl<I> Clone for Cloned<I> where
I: Clone,
impl<I> Clone for Copied<I> where
I: Clone,
impl<I> Clone for Cycle<I> where
I: Clone,
impl<I> Clone for Enumerate<I> where
I: Clone,
impl<I> Clone for Fuse<I> where
I: Clone,
impl<I> Clone for Intersperse<I> where
I: Clone + Iterator,
<I as Iterator>::Item: Clone,
<I as Iterator>::Item: Clone,
impl<I> Clone for Peekable<I> where
I: Clone + Iterator,
<I as Iterator>::Item: Clone,
impl<I> Clone for Skip<I> where
I: Clone,
impl<I> Clone for StepBy<I> where
I: Clone,
impl<I> Clone for Take<I> where
I: Clone,
impl<I, F> Clone for FilterMap<I, F> where
I: Clone,
F: Clone,
impl<I, F> Clone for Inspect<I, F> where
I: Clone,
F: Clone,
impl<I, F> Clone for Map<I, F> where
I: Clone,
F: Clone,
impl<I, G> Clone for IntersperseWith<I, G> where
I: Iterator + Clone,
G: Clone,
<I as Iterator>::Item: Clone,
impl<I, P> Clone for Filter<I, P> where
I: Clone,
P: Clone,
impl<I, P> Clone for MapWhile<I, P> where
I: Clone,
P: Clone,
impl<I, P> Clone for SkipWhile<I, P> where
I: Clone,
P: Clone,
impl<I, P> Clone for TakeWhile<I, P> where
I: Clone,
P: Clone,
impl<I, St, F> Clone for Scan<I, St, F> where
I: Clone,
St: Clone,
F: Clone,
impl<I, U> Clone for Flatten<I> where
I: Clone + Iterator,
U: Clone + Iterator,
<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<I, U, F> Clone for FlatMap<I, U, F> where
I: Clone,
F: Clone,
U: Clone + IntoIterator,
<U as IntoIterator>::IntoIter: Clone,
impl<Idx> Clone for std::ops::Range<Idx> where
Idx: Clone,
impl<Idx> Clone for RangeFrom<Idx> where
Idx: Clone,
impl<Idx> Clone for RangeInclusive<Idx> where
Idx: Clone,
impl<Idx> Clone for RangeTo<Idx> where
Idx: Clone,
impl<Idx> Clone for RangeToInclusive<Idx> where
Idx: Clone,
impl<K> Clone for std::collections::hash_set::Iter<'_, K>
impl<K, V> Clone for std::collections::btree_map::Iter<'_, K, V>
impl<K, V> Clone for std::collections::btree_map::Keys<'_, K, V>
impl<K, V> Clone for std::collections::btree_map::Range<'_, K, V>
impl<K, V> Clone for std::collections::btree_map::Values<'_, K, V>
impl<K, V> Clone for std::collections::hash_map::Iter<'_, K, V>
impl<K, V> Clone for std::collections::hash_map::Keys<'_, K, V>
impl<K, V> Clone for std::collections::hash_map::Values<'_, K, V>
impl<K, V, A> Clone for BTreeMap<K, V, A> where
K: Clone,
V: Clone,
A: Allocator + Clone,
impl<K, V, S> Clone for HashMap<K, V, S> where
K: Clone,
V: Clone,
S: Clone,
impl<P> Clone for Pin<P> where
P: Clone,
impl<Ret, T> Clone for fn (T1, T2, ..., Tn) -> Ret
This trait is implemented on function pointers with any number of arguments.
impl<T> !Clone for &mut T where
T: ?Sized,
Shared references can be cloned, but mutable references cannot!
impl<T> Clone for Bound<T> where
T: Clone,
impl<T> Clone for Option<T> where
T: Clone,
impl<T> Clone for Poll<T> where
T: Clone,
impl<T> Clone for *const T where
T: ?Sized,
impl<T> Clone for *mut T where
T: ?Sized,
impl<T> Clone for &T where
T: ?Sized,
Shared references can be cloned, but mutable references cannot!
impl<T> Clone for Cell<T> where
T: Copy,
impl<T> Clone for OnceCell<T> where
T: Clone,
impl<T> Clone for RefCell<T> where
T: Clone,
impl<T> Clone for Reverse<T> where
T: Clone,
impl<T> Clone for std::collections::binary_heap::IntoIter<T> where
T: Clone,
impl<T> Clone for IntoIterSorted<T> where
T: Clone,
impl<T> Clone for std::collections::binary_heap::Iter<'_, T>
impl<T> Clone for std::collections::btree_set::Iter<'_, T>
impl<T> Clone for std::collections::btree_set::Range<'_, T>
impl<T> Clone for std::collections::btree_set::SymmetricDifference<'_, T>
impl<T> Clone for std::collections::btree_set::Union<'_, T>
impl<T> Clone for std::collections::linked_list::Cursor<'_, T>
impl<T> Clone for std::collections::linked_list::IntoIter<T> where
T: Clone,
impl<T> Clone for std::collections::linked_list::Iter<'_, T>
impl<T> Clone for BinaryHeap<T> where
T: Clone,
impl<T> Clone for LinkedList<T> where
T: Clone,
impl<T> Clone for std::collections::vec_deque::Iter<'_, T>
impl<T> Clone for Pending<T>
impl<T> Clone for Ready<T> where
T: Clone,
impl<T> Clone for std::io::Cursor<T> where
T: Clone,
impl<T> Clone for std::iter::Empty<T>
impl<T> Clone for Once<T> where
T: Clone,
impl<T> Clone for Rev<T> where
T: Clone,
impl<T> Clone for PhantomData<T> where
T: ?Sized,
impl<T> Clone for Discriminant<T>
impl<T> Clone for ManuallyDrop<T> where
T: Clone + ?Sized,
impl<T> Clone for Saturating<T> where
T: Clone,
impl<T> Clone for Wrapping<T> where
T: Clone,
impl<T> Clone for NonNull<T> where
T: ?Sized,
impl<T> Clone for Rc<T> where
T: ?Sized,
impl<T> Clone for std::rc::Weak<T> where
T: ?Sized,
impl<T> Clone for std::result::IntoIter<T> where
T: Clone,
impl<T> Clone for std::result::Iter<'_, T>
impl<T> Clone for Chunks<'_, T>
impl<T> Clone for ChunksExact<'_, T>
impl<T> Clone for std::slice::Iter<'_, T>
impl<T> Clone for RChunks<'_, T>
impl<T> Clone for Windows<'_, T>
impl<T> Clone for Sender<T>
impl<T> Clone for SyncSender<T>
impl<T> Clone for Arc<T> where
T: ?Sized,
impl<T> Clone for std::sync::Weak<T> where
T: ?Sized,
impl<T> Clone for MaybeUninit<T> where
T: Copy,
impl<T, A> Clone for Box<[T], A> where
T: Clone,
A: Allocator + Clone,
impl<T, A> Clone for Box<T, A> where
T: Clone,
A: Allocator + Clone,
impl<T, A> Clone for std::collections::btree_set::Difference<'_, T, A> where
A: Allocator + Clone,
impl<T, A> Clone for std::collections::btree_set::Intersection<'_, T, A> where
A: Allocator + Clone,
impl<T, A> Clone for BTreeSet<T, A> where
T: Clone,
A: Allocator + Clone,
impl<T, A> Clone for VecDeque<T, A> where
T: Clone,
A: Allocator + Clone,
impl<T, A> Clone for std::collections::vec_deque::IntoIter<T, A> where
T: Clone,
A: Clone + Allocator,
impl<T, A> Clone for std::vec::IntoIter<T, A> where
T: Clone,
A: Allocator + Clone,
impl<T, A> Clone for Vec<T, A> where
T: Clone,
A: Allocator + Clone,
impl<T, E> Clone for Result<T, E> where
T: Clone,
E: Clone,
impl<T, F> Clone for Successors<T, F> where
T: Clone,
F: Clone,
impl<T, P> Clone for std::slice::RSplit<'_, T, P> where
P: Clone + FnMut(&T) -> bool,
impl<T, P> Clone for std::slice::Split<'_, T, P> where
P: Clone + FnMut(&T) -> bool,
impl<T, P> Clone for std::slice::SplitInclusive<'_, T, P> where
P: Clone + FnMut(&T) -> bool,
impl<T, S> Clone for std::collections::hash_set::Difference<'_, T, S>
impl<T, S> Clone for HashSet<T, S> where
T: Clone,
S: Clone,
impl<T, S> Clone for std::collections::hash_set::Intersection<'_, T, S>
impl<T, S> Clone for std::collections::hash_set::SymmetricDifference<'_, T, S>
impl<T, S> Clone for std::collections::hash_set::Union<'_, T, S>
impl<T, const LANES: usize> Clone for Mask<T, LANES> where
T: MaskElement,
LaneCount<LANES>: SupportedLaneCount,
impl<T, const LANES: usize> Clone for Simd<T, LANES> where
T: SimdElement,
LaneCount<LANES>: SupportedLaneCount,
impl<T, const N: usize> Clone for [T; N] where
T: Clone,
impl<T, const N: usize> Clone for std::array::IntoIter<T, N> where
T: Clone,
impl<T, const N: usize> Clone for ArrayChunks<'_, T, N>
impl<T: Clone> Clone for TrySendError<T>
impl<T: Clone> Clone for (T1, T2, ..., Tn)
This trait is implemented on arbitrary-length tuples.