Trait sp_std::clone::Clone

1.0.0 · source · [−]

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)
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 Clone themselves. Note that variables captured by shared reference always implement Clone (even if the referent doesn’t), while variables captured by mutable reference never implement Clone.

Trait sp_std::clone::Clone

Required methods

fn clone(&self) -> Self

Provided methods

fn clone_from(&mut self, source: &Self)

Implementations on Foreign Types

impl<'_, T, S> Clone for Difference<'_, T, S>

pub fn clone(&self) -> Difference<'_, T, S>ⓘNotable traits for Difference<'a, T, S>impl<'a, T, S> Iterator for Difference<'a, T, S> where T: Eq + Hash, S: BuildHasher, type Item = &'a T;

impl Clone for Thread

pub fn clone(&self) -> Thread

impl<'_, T, S> Clone for Intersection<'_, T, S>

pub fn clone(&self) -> Intersection<'_, T, S>ⓘNotable traits for Intersection<'a, T, S>impl<'a, T, S> Iterator for Intersection<'a, T, S> where T: Eq + Hash, S: BuildHasher, type Item = &'a T;

impl Clone for RandomState

pub fn clone(&self) -> RandomState

impl Clone for Empty

pub fn clone(&self) -> Empty

impl Clone for BacktraceStyle

pub fn clone(&self) -> BacktraceStyle

impl<'a> Clone for Prefix<'a>

pub fn clone(&self) -> Prefix<'a>

impl<'a> Clone for IoSlice<'a>

pub fn clone(&self) -> IoSlice<'a>

impl Clone for DefaultHasher

pub fn clone(&self) -> DefaultHasher

impl Clone for SocketAddr

pub fn clone(&self) -> SocketAddr

impl Clone for AddrParseError

pub fn clone(&self) -> AddrParseError

impl<'_, K> Clone for Iter<'_, K>

pub fn clone(&self) -> Iter<'_, K>ⓘNotable traits for Iter<'a, K>impl<'a, K> Iterator for Iter<'a, K> type Item = &'a K;

impl Clone for AccessError

pub fn clone(&self) -> AccessError

impl Clone for SystemTimeError

pub fn clone(&self) -> SystemTimeError

impl Clone for Ipv4Addr

pub fn clone(&self) -> Ipv4Addr

impl<'_, K, V> Clone for Iter<'_, K, V>

pub fn clone(&self) -> Iter<'_, K, V>ⓘNotable traits for Iter<'a, K, V>impl<'a, K, V> Iterator for Iter<'a, K, V> type Item = (&'a K, &'a V);

impl Clone for Output

pub fn clone(&self) -> Output

impl<K, V, S> Clone for HashMap<K, V, S> where K: Clone, V: Clone, S: Clone,

pub fn clone(&self) -> HashMap<K, V, S>

pub fn clone_from(&mut self, other: &HashMap<K, V, S>)

impl Clone for OpenOptions

pub fn clone(&self) -> OpenOptions

impl Clone for PathBuf

pub fn clone(&self) -> PathBuf

pub fn clone_from(&mut self, source: &PathBuf)

impl<'_, K, V> Clone for Keys<'_, K, V>

pub fn clone(&self) -> Keys<'_, K, V>ⓘNotable traits for Keys<'a, K, V>impl<'a, K, V> Iterator for Keys<'a, K, V> type Item = &'a K;

impl Clone for stat

pub fn clone(&self) -> stat

impl Clone for SocketCred

pub fn clone(&self) -> SocketCred

impl<'a> Clone for Components<'a>

pub fn clone(&self) -> Components<'a>ⓘNotable traits for Components<'a>impl<'a> Iterator for Components<'a> type Item = Component<'a>;

impl<'a> Clone for Iter<'a>

pub fn clone(&self) -> Iter<'a>ⓘNotable traits for Iter<'a>impl<'a> Iterator for Iter<'a> type Item = &'a OsStr;

impl<'a> Clone for PrefixComponent<'a>

pub fn clone(&self) -> PrefixComponent<'a>

impl Clone for Ipv6MulticastScope

pub fn clone(&self) -> Ipv6MulticastScope

impl Clone for ThreadId

pub fn clone(&self) -> ThreadId

impl Clone for IntoStringError

pub fn clone(&self) -> IntoStringError

impl<T> Clone for SyncOnceCell<T> where T: Clone,

pub fn clone(&self) -> SyncOnceCell<T>

impl Clone for ExitCode

pub fn clone(&self) -> ExitCode

impl Clone for VarError

pub fn clone(&self) -> VarError

impl Clone for NulError

pub fn clone(&self) -> NulError

impl<'fd> Clone for BorrowedFd<'fd>

pub fn clone(&self) -> BorrowedFd<'fd>

impl<T, S> Clone for HashSet<T, S> where T: Clone, S: Clone,

pub fn clone(&self) -> HashSet<T, S>

pub fn clone_from(&mut self, other: &HashSet<T, S>)

impl Clone for Permissions

pub fn clone(&self) -> Difference<'_, T, S>ⓘNotable traits for Difference<'a, T, S>`impl<'a, T, S> Iterator for Difference<'a, T, S> where T: Eq + Hash, S: BuildHasher, type Item = &'a T;`

pub fn clone(&self) -> Intersection<'_, T, S>ⓘNotable traits for Intersection<'a, T, S>`impl<'a, T, S> Iterator for Intersection<'a, T, S> where T: Eq + Hash, S: BuildHasher, type Item = &'a T;`

pub fn clone(&self) -> Iter<'_, K>ⓘNotable traits for Iter<'a, K>`impl<'a, K> Iterator for Iter<'a, K> type Item = &'a K;`

pub fn clone(&self) -> Iter<'_, K, V>ⓘNotable traits for Iter<'a, K, V>`impl<'a, K, V> Iterator for Iter<'a, K, V> type Item = (&'a K, &'a V);`

impl<K, V, S> Clone for HashMap<K, V, S> where
K: Clone,
V: Clone,
S: Clone,

pub fn clone(&self) -> Keys<'_, K, V>ⓘNotable traits for Keys<'a, K, V>`impl<'a, K, V> Iterator for Keys<'a, K, V> type Item = &'a K;`

pub fn clone(&self) -> Components<'a>ⓘNotable traits for Components<'a>`impl<'a> Iterator for Components<'a> type Item = Component<'a>;`

pub fn clone(&self) -> Iter<'a>ⓘNotable traits for Iter<'a>`impl<'a> Iterator for Iter<'a> type Item = &'a OsStr;`

impl<T> Clone for SyncOnceCell<T> where
T: Clone,

impl<T, S> Clone for HashSet<T, S> where
T: Clone,
S: Clone,

pub fn clone(&self) -> Values<'_, K, V>ⓘNotable traits for Values<'a, K, V>`impl<'a, K, V> Iterator for Values<'a, K, V> type Item = &'a V;`

pub fn clone(&self) -> SymmetricDifference<'_, T, S>ⓘNotable traits for SymmetricDifference<'a, T, S>`impl<'a, T, S> Iterator for SymmetricDifference<'a, T, S> where T: Eq + Hash, S: BuildHasher, type Item = &'a T;`

pub fn clone(&self) -> Union<'_, T, S>ⓘNotable traits for Union<'a, T, S>`impl<'a, T, S> Iterator for Union<'a, T, S> where T: Eq + Hash, S: BuildHasher, type Item = &'a T;`

impl<T> Clone for Cursor<T> where
T: Clone,

pub fn clone(&self) -> Chain<'a>ⓘNotable traits for Chain<'a>`impl<'a> Iterator for Chain<'a> type Item = &'a (dyn Error + 'static);`

pub fn clone(&self) -> Ancestors<'a>ⓘNotable traits for Ancestors<'a>`impl<'a> Iterator for Ancestors<'a> type Item = &'a Path;`