Trait core::clone::Clone 1.0.0
[−]
[src]
#[lang = "clone"]pub trait Clone: Sized { 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 derive
d
implementation of clone
calls clone
on each field.
Closures
Closure types automatically implement Clone
if they capture no value from the environment
or if all such captured values implement Clone
themselves.
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 derive
d, but can be implemented as:
#[derive(Copy)] struct Stats { frequencies: [i32; 100], } impl Clone for Stats { fn clone(&self) -> Stats { *self } }Run
Required Methods
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.
Implementors
impl Clone for ParseFloatError
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 NonZeroI8
impl Clone for NonZeroI16
impl Clone for NonZeroI32
impl Clone for NonZeroI64
impl Clone for NonZeroI128
impl Clone for NonZeroIsize
impl<T: Clone> Clone for Wrapping<T>
impl Clone for FpCategory
impl Clone for TryFromIntError
impl Clone for ParseIntError
impl<T> Clone for Discriminant<T>
impl<T: Clone> Clone for ManuallyDrop<T>
impl<T: Clone + Zeroable> Clone for NonZero<T>
impl<T: ?Sized> Clone for Unique<T>
impl<T: ?Sized> Clone for NonNull<T>
impl<T: ?Sized> Clone for PhantomData<T>
impl<Y: Clone, R: Clone> Clone for GeneratorState<Y, R>
impl Clone for RangeFull
impl<Idx: Clone> Clone for Range<Idx>
impl<Idx: Clone> Clone for RangeFrom<Idx>
impl<Idx: Clone> Clone for RangeTo<Idx>
impl<Idx: Clone> Clone for RangeInclusive<Idx>
impl<Idx: Clone> Clone for RangeToInclusive<Idx>
impl<T: Clone> Clone for Bound<T>
impl Clone for core::cmp::Ordering
impl<T: Clone> Clone for Reverse<T>
impl Clone for TypeId
impl Clone for TryFromSliceError
impl Clone for core::sync::atomic::Ordering
impl<T: Copy> Clone for Cell<T>
impl<T: Clone> Clone for RefCell<T>
impl Clone for ParseCharError
impl Clone for CharTryFromError
impl Clone for EscapeUnicode
impl Clone for EscapeDefault
impl Clone for EscapeDebug
impl<I: Clone + Iterator<Item = u8>> Clone for DecodeUtf8<I>
impl<A: Clone> Clone for Repeat<A>
impl<F: Clone> Clone for RepeatWith<F>
impl<T> Clone for Empty<T>
impl<T: Clone> Clone for Once<T>
impl<T: Clone> Clone for Rev<T>
impl<I: Clone> Clone for Cloned<I>
impl<I: Clone> Clone for Cycle<I>
impl<I: Clone> Clone for StepBy<I>
impl<A: Clone, B: Clone> Clone for Chain<A, B>
impl<A: Clone, B: Clone> Clone for Zip<A, B>
impl<I: Clone, F: Clone> Clone for Map<I, F>
impl<I: Clone, P: Clone> Clone for Filter<I, P>
impl<I: Clone, F: Clone> Clone for FilterMap<I, F>
impl<I: Clone> Clone for Enumerate<I>
impl<I: Clone + Iterator> Clone for Peekable<I> where
I::Item: Clone,impl<I: Clone, P: Clone> Clone for SkipWhile<I, P>
impl<I: Clone, P: Clone> Clone for TakeWhile<I, P>
impl<I: Clone> Clone for Skip<I>
impl<I: Clone> Clone for Take<I>
impl<I: Clone, St: Clone, F: Clone> Clone for Scan<I, St, F>
impl<I: Clone, U: Clone + IntoIterator, F: Clone> Clone for FlatMap<I, U, F> where
<U as IntoIterator>::IntoIter: Clone,impl<I, U> Clone for Flatten<I> where
I: Iterator + Clone,
U: Iterator + Clone,
I::Item: IntoIterator<IntoIter = U, Item = U::Item>,impl<I: Clone> Clone for Fuse<I>
impl<I: Clone, F: Clone> Clone for Inspect<I, F>
impl<T: Clone> Clone for Option<T>
impl<'a, A> Clone for core::option::Iter<'a, A>
impl<A: Clone> Clone for core::option::IntoIter<A>
impl Clone for NoneError
impl Clone for TraitObject
impl<T: Clone, E: Clone> Clone for Result<T, E>
impl<'a, T> Clone for core::result::Iter<'a, T>
impl<T: Clone> Clone for core::result::IntoIter<T>
impl<'a, T> Clone for core::slice::Iter<'a, T>
impl<'a, T, P> Clone for core::slice::Split<'a, T, P> where
P: Clone + FnMut(&T) -> bool,impl<'a, T: Clone + 'a, P: Clone> Clone for core::slice::RSplit<'a, T, P> where
P: FnMut(&T) -> bool,impl<'a, T> Clone for Windows<'a, T>
impl<'a, T> Clone for Chunks<'a, T>
impl<'a, T> Clone for ExactChunks<'a, T>
impl Clone for SearchStep
impl<'a> Clone for CharSearcher<'a>
impl<'a, 'b> Clone for CharSliceSearcher<'a, 'b>
impl<'a, F: Clone> Clone for CharPredicateSearcher<'a, F> where
F: FnMut(char) -> bool,impl<'a, 'b> Clone for StrSearcher<'a, 'b>
impl Clone for ParseBoolError
impl Clone for Utf8Error
impl<'a> Clone for Chars<'a>
impl<'a> Clone for CharIndices<'a>
impl<'a> Clone for Bytes<'a>
impl<'a, P: Pattern<'a>> Clone for core::str::Split<'a, P> where
P::Searcher: Clone,impl<'a, P: Pattern<'a>> Clone for core::str::RSplit<'a, P> where
P::Searcher: Clone,impl<'a, P: Pattern<'a>> Clone for SplitTerminator<'a, P> where
P::Searcher: Clone,impl<'a, P: Pattern<'a>> Clone for RSplitTerminator<'a, P> where
P::Searcher: Clone,impl<'a, P: Pattern<'a>> Clone for SplitN<'a, P> where
P::Searcher: Clone,impl<'a, P: Pattern<'a>> Clone for RSplitN<'a, P> where
P::Searcher: Clone,impl<'a, P: Pattern<'a>> Clone for MatchIndices<'a, P> where
P::Searcher: Clone,impl<'a, P: Pattern<'a>> Clone for RMatchIndices<'a, P> where
P::Searcher: Clone,impl<'a, P: Pattern<'a>> Clone for Matches<'a, P> where
P::Searcher: Clone,impl<'a, P: Pattern<'a>> Clone for RMatches<'a, P> where
P::Searcher: Clone,impl<'a> Clone for Lines<'a>
impl<'a> Clone for LinesAny<'a>
impl Clone for SipHasher
impl<H> Clone for BuildHasherDefault<H>
impl Clone for Error
impl<'a> Clone for Arguments<'a>
impl Clone for Duration
impl Clone for Layout
impl Clone for AllocErr
impl Clone for CannotReallocInPlace
impl Clone for CollectionAllocErr
impl Clone for i8x2
impl Clone for u8x2
impl Clone for b8x2
impl Clone for i16x2
impl Clone for u16x2
impl Clone for i8x4
impl Clone for u8x4
impl Clone for b8x4
impl Clone for i8x8
impl Clone for u8x8
impl Clone for b8x8
impl Clone for i16x4
impl Clone for u16x4
impl Clone for i32x2
impl Clone for u32x2
impl Clone for f32x2
impl Clone for i8x16
impl Clone for u8x16
impl Clone for b8x16
impl Clone for i16x8
impl Clone for u16x8
impl Clone for i32x4
impl Clone for u32x4
impl Clone for f32x4
impl Clone for i64x2
impl Clone for u64x2
impl Clone for f64x2
impl Clone for i8x32
impl Clone for u8x32
impl Clone for b8x32
impl Clone for i16x16
impl Clone for u16x16
impl Clone for i32x8
impl Clone for u32x8
impl Clone for f32x8
impl Clone for i64x4
impl Clone for u64x4
impl Clone for f64x4
impl Clone for i8x64
impl Clone for u8x64
impl Clone for b8x64
impl Clone for i16x32
impl Clone for u16x32
impl Clone for i32x16
impl Clone for u32x16
impl Clone for f32x16
impl Clone for i64x8
impl Clone for u64x8
impl Clone for f64x8
impl Clone for CpuidResult
impl Clone for __m64
impl Clone for __m128i
impl Clone for __m128
impl Clone for __m128d
impl Clone for __m256i
impl Clone for __m256
impl Clone for __m256d