Enum Cow
pub enum Cow<'a, B>{
Borrowed(&'a B),
Owned(<B as ToOwned>::Owned),
}Expand description
A clone-on-write smart pointer.
The type Cow is a smart pointer providing clone-on-write functionality: it
can enclose and provide immutable access to borrowed data, and clone the
data lazily when mutation or ownership is required. The type is designed to
work with general borrowed data via the Borrow trait.
Cow implements Deref, which means that you can call
non-mutating methods directly on the data it encloses. If mutation
is desired, to_mut will obtain a mutable reference to an owned
value, cloning if necessary.
If you need reference-counting pointers, note that
Rc::make_mut and
Arc::make_mut can provide clone-on-write
functionality as well.
§Examples
use std::borrow::Cow;
fn abs_all(input: &mut Cow<'_, [i32]>) {
for i in 0..input.len() {
let v = input[i];
if v < 0 {
// Clones into a vector if not already owned.
input.to_mut()[i] = -v;
}
}
}
// No clone occurs because `input` doesn't need to be mutated.
let slice = [0, 1, 2];
let mut input = Cow::from(&slice[..]);
abs_all(&mut input);
// Clone occurs because `input` needs to be mutated.
let slice = [-1, 0, 1];
let mut input = Cow::from(&slice[..]);
abs_all(&mut input);
// No clone occurs because `input` is already owned.
let mut input = Cow::from(vec![-1, 0, 1]);
abs_all(&mut input);Another example showing how to keep Cow in a struct:
use std::borrow::Cow;
struct Items<'a, X> where [X]: ToOwned<Owned = Vec<X>> {
values: Cow<'a, [X]>,
}
impl<'a, X: Clone + 'a> Items<'a, X> where [X]: ToOwned<Owned = Vec<X>> {
fn new(v: Cow<'a, [X]>) -> Self {
Items { values: v }
}
}
// Creates a container from borrowed values of a slice
let readonly = [1, 2];
let borrowed = Items::new((&readonly[..]).into());
match borrowed {
Items { values: Cow::Borrowed(b) } => println!("borrowed {b:?}"),
_ => panic!("expect borrowed value"),
}
let mut clone_on_write = borrowed;
// Mutates the data from slice into owned vec and pushes a new value on top
clone_on_write.values.to_mut().push(3);
println!("clone_on_write = {:?}", clone_on_write.values);
// The data was mutated. Let's check it out.
match clone_on_write {
Items { values: Cow::Owned(_) } => println!("clone_on_write contains owned data"),
_ => panic!("expect owned data"),
}Variants§
Implementations§
§impl<B> Cow<'_, B>
impl<B> Cow<'_, B>
pub const fn is_borrowed(c: &Cow<'_, B>) -> bool
🔬This is a nightly-only experimental API. (cow_is_borrowed)
pub const fn is_borrowed(c: &Cow<'_, B>) -> bool
cow_is_borrowed)Returns true if the data is borrowed, i.e. if to_mut would require additional work.
Note: this is an associated function, which means that you have to call
it as Cow::is_borrowed(&c) instead of c.is_borrowed(). This is so
that there is no conflict with a method on the inner type.
§Examples
#![feature(cow_is_borrowed)]
use std::borrow::Cow;
let cow = Cow::Borrowed("moo");
assert!(Cow::is_borrowed(&cow));
let bull: Cow<'_, str> = Cow::Owned("...moo?".to_string());
assert!(!Cow::is_borrowed(&bull));pub const fn is_owned(c: &Cow<'_, B>) -> bool
🔬This is a nightly-only experimental API. (cow_is_borrowed)
pub const fn is_owned(c: &Cow<'_, B>) -> bool
cow_is_borrowed)Returns true if the data is owned, i.e. if to_mut would be a no-op.
Note: this is an associated function, which means that you have to call
it as Cow::is_owned(&c) instead of c.is_owned(). This is so that
there is no conflict with a method on the inner type.
§Examples
#![feature(cow_is_borrowed)]
use std::borrow::Cow;
let cow: Cow<'_, str> = Cow::Owned("moo".to_string());
assert!(Cow::is_owned(&cow));
let bull = Cow::Borrowed("...moo?");
assert!(!Cow::is_owned(&bull));1.0.0pub fn to_mut(&mut self) -> &mut <B as ToOwned>::Owned
pub fn to_mut(&mut self) -> &mut <B as ToOwned>::Owned
Acquires a mutable reference to the owned form of the data.
Clones the data if it is not already owned.
§Examples
use std::borrow::Cow;
let mut cow = Cow::Borrowed("foo");
cow.to_mut().make_ascii_uppercase();
assert_eq!(
cow,
Cow::Owned(String::from("FOO")) as Cow<'_, str>
);1.0.0pub fn into_owned(self) -> <B as ToOwned>::Owned
pub fn into_owned(self) -> <B as ToOwned>::Owned
Extracts the owned data.
Clones the data if it is not already owned.
§Examples
Calling into_owned on a Cow::Borrowed returns a clone of the borrowed data:
use std::borrow::Cow;
let s = "Hello world!";
let cow = Cow::Borrowed(s);
assert_eq!(
cow.into_owned(),
String::from(s)
);Calling into_owned on a Cow::Owned returns the owned data. The data is moved out of the
Cow without being cloned.
use std::borrow::Cow;
let s = "Hello world!";
let cow: Cow<'_, str> = Cow::Owned(String::from(s));
assert_eq!(
cow.into_owned(),
String::from(s)
);Trait Implementations§
1.14.0§impl<'a> AddAssign<&'a str> for Cow<'a, str>
Available on non-no_global_oom_handling only.
impl<'a> AddAssign<&'a str> for Cow<'a, str>
no_global_oom_handling only.§fn add_assign(&mut self, rhs: &'a str)
fn add_assign(&mut self, rhs: &'a str)
+= operation. Read more1.14.0§impl<'a> AddAssign for Cow<'a, str>
Available on non-no_global_oom_handling only.
impl<'a> AddAssign for Cow<'a, str>
no_global_oom_handling only.§fn add_assign(&mut self, rhs: Cow<'a, str>)
fn add_assign(&mut self, rhs: Cow<'a, str>)
+= operation. Read moreSource§impl<'de, 'a, T> Deserialize<'de> for Cow<'a, T>
Available on crate features std or alloc only.
impl<'de, 'a, T> Deserialize<'de> for Cow<'a, T>
std or alloc only.Source§fn deserialize<D>(
deserializer: D,
) -> Result<Cow<'a, T>, <D as Deserializer<'de>>::Error>where
D: Deserializer<'de>,
fn deserialize<D>(
deserializer: D,
) -> Result<Cow<'a, T>, <D as Deserializer<'de>>::Error>where
D: Deserializer<'de>,
1.52.0§impl<'a> Extend<Cow<'a, OsStr>> for OsString
impl<'a> Extend<Cow<'a, OsStr>> for OsString
§fn extend_one(&mut self, item: A)
fn extend_one(&mut self, item: A)
extend_one)§fn extend_reserve(&mut self, additional: usize)
fn extend_reserve(&mut self, additional: usize)
extend_one)1.19.0§impl<'a> Extend<Cow<'a, str>> for String
Available on non-no_global_oom_handling only.
impl<'a> Extend<Cow<'a, str>> for String
no_global_oom_handling only.§fn extend_one(&mut self, s: Cow<'a, str>)
fn extend_one(&mut self, s: Cow<'a, str>)
extend_one)§fn extend_reserve(&mut self, additional: usize)
fn extend_reserve(&mut self, additional: usize)
extend_one)§impl<'a> From<&'a ByteString> for Cow<'a, ByteStr>
impl<'a> From<&'a ByteString> for Cow<'a, ByteStr>
§fn from(s: &'a ByteString) -> Cow<'a, ByteStr>
fn from(s: &'a ByteString) -> Cow<'a, ByteStr>
§impl<'a> From<ByteString> for Cow<'a, ByteStr>
impl<'a> From<ByteString> for Cow<'a, ByteStr>
§fn from(s: ByteString) -> Cow<'a, ByteStr>
fn from(s: ByteString) -> Cow<'a, ByteStr>
1.45.0§impl<T> From<Cow<'_, [T]>> for Box<[T]>where
T: Clone,
Available on non-no_global_oom_handling only.
impl<T> From<Cow<'_, [T]>> for Box<[T]>where
T: Clone,
no_global_oom_handling only.1.45.0§impl From<Cow<'_, str>> for Box<str>
Available on non-no_global_oom_handling only.
impl From<Cow<'_, str>> for Box<str>
no_global_oom_handling only.§fn from(cow: Cow<'_, str>) -> Box<str>
fn from(cow: Cow<'_, str>) -> Box<str>
Converts a Cow<'_, str> into a Box<str>
When cow is the Cow::Borrowed variant, this
conversion allocates on the heap and copies the
underlying str. Otherwise, it will try to reuse the owned
String’s allocation.
§Examples
use std::borrow::Cow;
let unboxed = Cow::Borrowed("hello");
let boxed: Box<str> = Box::from(unboxed);
println!("{boxed}");let unboxed = Cow::Owned("hello".to_string());
let boxed: Box<str> = Box::from(unboxed);
println!("{boxed}");1.14.0§impl<'a, T> From<Cow<'a, [T]>> for Vec<T>
impl<'a, T> From<Cow<'a, [T]>> for Vec<T>
§fn from(s: Cow<'a, [T]>) -> Vec<T>
fn from(s: Cow<'a, [T]>) -> Vec<T>
Converts a clone-on-write slice into a vector.
If s already owns a Vec<T>, it will be returned directly.
If s is borrowing a slice, a new Vec<T> will be allocated and
filled by cloning s’s items into it.
§Examples
let o: Cow<'_, [i32]> = Cow::Owned(vec![1, 2, 3]);
let b: Cow<'_, [i32]> = Cow::Borrowed(&[1, 2, 3]);
assert_eq!(Vec::from(o), Vec::from(b));1.14.0§impl<'a> From<Cow<'a, str>> for String
Available on non-no_global_oom_handling only.
impl<'a> From<Cow<'a, str>> for String
no_global_oom_handling only.§fn from(s: Cow<'a, str>) -> String
fn from(s: Cow<'a, str>) -> String
Converts a clone-on-write string to an owned
instance of String.
This extracts the owned string, clones the string if it is not already owned.
§Example
// If the string is not owned...
let cow: Cow<'_, str> = Cow::Borrowed("eggplant");
// It will allocate on the heap and copy the string.
let owned: String = String::from(cow);
assert_eq!(&owned[..], "eggplant");Source§impl<'a> From<Cow<'a, str>> for Value
impl<'a> From<Cow<'a, str>> for Value
Source§fn from(f: Cow<'a, str>) -> Value
fn from(f: Cow<'a, str>) -> Value
Convert copy-on-write string to Value::String.
§Examples
use serde_json::Value;
use std::borrow::Cow;
let s: Cow<str> = Cow::Borrowed("lorem");
let x: Value = s.into();use serde_json::Value;
use std::borrow::Cow;
let s: Cow<str> = Cow::Owned("lorem".to_owned());
let x: Value = s.into();1.22.0§impl<'a, 'b> From<Cow<'b, str>> for Box<dyn Error + 'a>
Available on non-no_global_oom_handling only.
impl<'a, 'b> From<Cow<'b, str>> for Box<dyn Error + 'a>
no_global_oom_handling only.1.22.0§impl<'a, 'b> From<Cow<'b, str>> for Box<dyn Error + Sync + Send + 'a>
Available on non-no_global_oom_handling only.
impl<'a, 'b> From<Cow<'b, str>> for Box<dyn Error + Sync + Send + 'a>
no_global_oom_handling only.§fn from(err: Cow<'b, str>) -> Box<dyn Error + Sync + Send + 'a>
fn from(err: Cow<'b, str>) -> Box<dyn Error + Sync + Send + 'a>
Converts a Cow into a box of dyn Error + Send + Sync.
§Examples
use std::error::Error;
use std::borrow::Cow;
let a_cow_str_error = Cow::from("a str error");
let a_boxed_error = Box::<dyn Error + Send + Sync>::from(a_cow_str_error);
assert!(
size_of::<Box<dyn Error + Send + Sync>>() == size_of_val(&a_boxed_error))1.12.0§impl<'a, 'b> FromIterator<&'b str> for Cow<'a, str>
Available on non-no_global_oom_handling only.
impl<'a, 'b> FromIterator<&'b str> for Cow<'a, str>
no_global_oom_handling only.§impl<'a> FromIterator<AsciiChar> for Cow<'a, str>
Available on non-no_global_oom_handling only.
impl<'a> FromIterator<AsciiChar> for Cow<'a, str>
no_global_oom_handling only.1.52.0§impl<'a> FromIterator<Cow<'a, OsStr>> for OsString
impl<'a> FromIterator<Cow<'a, OsStr>> for OsString
1.80.0§impl<'a> FromIterator<Cow<'a, str>> for Box<str>
Available on non-no_global_oom_handling only.
impl<'a> FromIterator<Cow<'a, str>> for Box<str>
no_global_oom_handling only.1.19.0§impl<'a> FromIterator<Cow<'a, str>> for String
Available on non-no_global_oom_handling only.
impl<'a> FromIterator<Cow<'a, str>> for String
no_global_oom_handling only.1.12.0§impl<'a> FromIterator<String> for Cow<'a, str>
Available on non-no_global_oom_handling only.
impl<'a> FromIterator<String> for Cow<'a, str>
no_global_oom_handling only.1.0.0§impl<'a, T> FromIterator<T> for Cow<'a, [T]>where
T: Clone,
impl<'a, T> FromIterator<T> for Cow<'a, [T]>where
T: Clone,
1.12.0§impl<'a> FromIterator<char> for Cow<'a, str>
Available on non-no_global_oom_handling only.
impl<'a> FromIterator<char> for Cow<'a, str>
no_global_oom_handling only.Source§impl<'a> FromPyObjectBound<'a, '_> for Cow<'a, [u8]>
Special-purpose trait impl to efficiently handle both bytes and bytearray
impl<'a> FromPyObjectBound<'a, '_> for Cow<'a, [u8]>
Special-purpose trait impl to efficiently handle both bytes and bytearray
If the source object is a bytes object, the Cow will be borrowed and
pointing into the source object, and no copying or heap allocations will happen.
If it is a bytearray, its contents will be copied to an owned Cow.
Source§impl<'a> FromPyObjectBound<'a, '_> for Cow<'a, str>
impl<'a> FromPyObjectBound<'a, '_> for Cow<'a, str>
Source§impl<'de, 'a, E> IntoDeserializer<'de, E> for Cow<'a, str>where
E: Error,
Available on crate features std or alloc only.
impl<'de, 'a, E> IntoDeserializer<'de, E> for Cow<'a, str>where
E: Error,
std or alloc only.Source§type Deserializer = CowStrDeserializer<'a, E>
type Deserializer = CowStrDeserializer<'a, E>
Source§fn into_deserializer(self) -> CowStrDeserializer<'a, E>
fn into_deserializer(self) -> CowStrDeserializer<'a, E>
Source§impl<'py> IntoPyObject<'py> for &Cow<'_, OsStr>
impl<'py> IntoPyObject<'py> for &Cow<'_, OsStr>
Source§type Output = Bound<'py, <&Cow<'_, OsStr> as IntoPyObject<'py>>::Target>
type Output = Bound<'py, <&Cow<'_, OsStr> as IntoPyObject<'py>>::Target>
Source§type Error = Infallible
type Error = Infallible
Source§fn into_pyobject(
self,
py: Python<'py>,
) -> Result<<&Cow<'_, OsStr> as IntoPyObject<'py>>::Output, <&Cow<'_, OsStr> as IntoPyObject<'py>>::Error>
fn into_pyobject( self, py: Python<'py>, ) -> Result<<&Cow<'_, OsStr> as IntoPyObject<'py>>::Output, <&Cow<'_, OsStr> as IntoPyObject<'py>>::Error>
Source§impl<'py> IntoPyObject<'py> for &Cow<'_, Path>
impl<'py> IntoPyObject<'py> for &Cow<'_, Path>
Source§impl<'py> IntoPyObject<'py> for &Cow<'_, str>
impl<'py> IntoPyObject<'py> for &Cow<'_, str>
Source§type Output = Bound<'py, <&Cow<'_, str> as IntoPyObject<'py>>::Target>
type Output = Bound<'py, <&Cow<'_, str> as IntoPyObject<'py>>::Target>
Source§type Error = Infallible
type Error = Infallible
Source§fn into_pyobject(
self,
py: Python<'py>,
) -> Result<<&Cow<'_, str> as IntoPyObject<'py>>::Output, <&Cow<'_, str> as IntoPyObject<'py>>::Error>
fn into_pyobject( self, py: Python<'py>, ) -> Result<<&Cow<'_, str> as IntoPyObject<'py>>::Output, <&Cow<'_, str> as IntoPyObject<'py>>::Error>
Source§impl<'py, T> IntoPyObject<'py> for Cow<'_, [T]>
impl<'py, T> IntoPyObject<'py> for Cow<'_, [T]>
Source§impl<'py> IntoPyObject<'py> for Cow<'_, OsStr>
impl<'py> IntoPyObject<'py> for Cow<'_, OsStr>
Source§type Output = Bound<'py, <Cow<'_, OsStr> as IntoPyObject<'py>>::Target>
type Output = Bound<'py, <Cow<'_, OsStr> as IntoPyObject<'py>>::Target>
Source§type Error = Infallible
type Error = Infallible
Source§fn into_pyobject(
self,
py: Python<'py>,
) -> Result<<Cow<'_, OsStr> as IntoPyObject<'py>>::Output, <Cow<'_, OsStr> as IntoPyObject<'py>>::Error>
fn into_pyobject( self, py: Python<'py>, ) -> Result<<Cow<'_, OsStr> as IntoPyObject<'py>>::Output, <Cow<'_, OsStr> as IntoPyObject<'py>>::Error>
Source§impl<'py> IntoPyObject<'py> for Cow<'_, Path>
impl<'py> IntoPyObject<'py> for Cow<'_, Path>
Source§impl<'py> IntoPyObject<'py> for Cow<'_, str>
impl<'py> IntoPyObject<'py> for Cow<'_, str>
Source§type Output = Bound<'py, <Cow<'_, str> as IntoPyObject<'py>>::Target>
type Output = Bound<'py, <Cow<'_, str> as IntoPyObject<'py>>::Target>
Source§type Error = Infallible
type Error = Infallible
Source§fn into_pyobject(
self,
py: Python<'py>,
) -> Result<<Cow<'_, str> as IntoPyObject<'py>>::Output, <Cow<'_, str> as IntoPyObject<'py>>::Error>
fn into_pyobject( self, py: Python<'py>, ) -> Result<<Cow<'_, str> as IntoPyObject<'py>>::Output, <Cow<'_, str> as IntoPyObject<'py>>::Error>
1.0.0§impl<B> Ord for Cow<'_, B>
impl<B> Ord for Cow<'_, B>
§impl<'a> PartialEq<ByteString> for Cow<'_, [u8]>
impl<'a> PartialEq<ByteString> for Cow<'_, [u8]>
§impl<'a> PartialEq<ByteString> for Cow<'_, ByteStr>
impl<'a> PartialEq<ByteString> for Cow<'_, ByteStr>
§impl<'a> PartialEq<ByteString> for Cow<'_, str>
impl<'a> PartialEq<ByteString> for Cow<'_, str>
§impl<'a> PartialOrd<&'a ByteStr> for Cow<'a, [u8]>
impl<'a> PartialOrd<&'a ByteStr> for Cow<'a, [u8]>
§impl<'a> PartialOrd<&'a ByteStr> for Cow<'a, ByteStr>
impl<'a> PartialOrd<&'a ByteStr> for Cow<'a, ByteStr>
§impl<'a> PartialOrd<&'a ByteStr> for Cow<'a, str>
impl<'a> PartialOrd<&'a ByteStr> for Cow<'a, str>
1.8.0§impl<'a, 'b> PartialOrd<&'b OsStr> for Cow<'a, OsStr>
impl<'a, 'b> PartialOrd<&'b OsStr> for Cow<'a, OsStr>
1.8.0§impl<'a, 'b> PartialOrd<&'b OsStr> for Cow<'a, Path>
impl<'a, 'b> PartialOrd<&'b OsStr> for Cow<'a, Path>
1.8.0§impl<'a, 'b> PartialOrd<&'b Path> for Cow<'a, Path>
impl<'a, 'b> PartialOrd<&'b Path> for Cow<'a, Path>
1.8.0§impl<'a, 'b> PartialOrd<&'a Path> for Cow<'b, OsStr>
impl<'a, 'b> PartialOrd<&'a Path> for Cow<'b, OsStr>
§impl<'a> PartialOrd<ByteString> for Cow<'_, [u8]>
impl<'a> PartialOrd<ByteString> for Cow<'_, [u8]>
§impl<'a> PartialOrd<ByteString> for Cow<'_, ByteStr>
impl<'a> PartialOrd<ByteString> for Cow<'_, ByteStr>
§impl<'a> PartialOrd<ByteString> for Cow<'_, str>
impl<'a> PartialOrd<ByteString> for Cow<'_, str>
1.8.0§impl<'a, 'b> PartialOrd<Cow<'a, OsStr>> for &'b OsStr
impl<'a, 'b> PartialOrd<Cow<'a, OsStr>> for &'b OsStr
1.8.0§impl<'a, 'b> PartialOrd<Cow<'a, OsStr>> for OsStr
impl<'a, 'b> PartialOrd<Cow<'a, OsStr>> for OsStr
1.8.0§impl<'a> PartialOrd<Cow<'a, OsStr>> for Path
impl<'a> PartialOrd<Cow<'a, OsStr>> for Path
1.8.0§impl<'a> PartialOrd<Cow<'a, OsStr>> for PathBuf
impl<'a> PartialOrd<Cow<'a, OsStr>> for PathBuf
1.8.0§impl<'a, 'b> PartialOrd<Cow<'a, Path>> for &'b OsStr
impl<'a, 'b> PartialOrd<Cow<'a, Path>> for &'b OsStr
1.8.0§impl<'a, 'b> PartialOrd<Cow<'a, Path>> for &'b Path
impl<'a, 'b> PartialOrd<Cow<'a, Path>> for &'b Path
1.8.0§impl<'a> PartialOrd<Cow<'a, Path>> for OsStr
impl<'a> PartialOrd<Cow<'a, Path>> for OsStr
1.8.0§impl<'a> PartialOrd<Cow<'a, Path>> for Path
impl<'a> PartialOrd<Cow<'a, Path>> for Path
1.8.0§impl<'a> PartialOrd<Cow<'a, Path>> for PathBuf
impl<'a> PartialOrd<Cow<'a, Path>> for PathBuf
1.8.0§impl<'a, 'b> PartialOrd<Cow<'b, OsStr>> for &'a Path
impl<'a, 'b> PartialOrd<Cow<'b, OsStr>> for &'a Path
1.8.0§impl<'a, 'b> PartialOrd<OsStr> for Cow<'a, OsStr>
impl<'a, 'b> PartialOrd<OsStr> for Cow<'a, OsStr>
1.8.0§impl<'a> PartialOrd<OsStr> for Cow<'a, Path>
impl<'a> PartialOrd<OsStr> for Cow<'a, Path>
1.8.0§impl<'a, 'b> PartialOrd<OsString> for Cow<'a, OsStr>
impl<'a, 'b> PartialOrd<OsString> for Cow<'a, OsStr>
1.8.0§impl<'a> PartialOrd<OsString> for Cow<'a, Path>
impl<'a> PartialOrd<OsString> for Cow<'a, Path>
1.8.0§impl<'a> PartialOrd<Path> for Cow<'a, OsStr>
impl<'a> PartialOrd<Path> for Cow<'a, OsStr>
1.8.0§impl<'a> PartialOrd<Path> for Cow<'a, Path>
impl<'a> PartialOrd<Path> for Cow<'a, Path>
1.8.0§impl<'a> PartialOrd<PathBuf> for Cow<'a, OsStr>
impl<'a> PartialOrd<PathBuf> for Cow<'a, OsStr>
1.8.0§impl<'a> PartialOrd<PathBuf> for Cow<'a, Path>
impl<'a> PartialOrd<PathBuf> for Cow<'a, Path>
1.0.0§impl<'a, B> PartialOrd for Cow<'a, B>
impl<'a, B> PartialOrd for Cow<'a, B>
Source§impl<'a, T> Serialize for Cow<'a, T>
Available on crate features std or alloc only.
impl<'a, T> Serialize for Cow<'a, T>
std or alloc only.Source§fn serialize<S>(
&self,
serializer: S,
) -> Result<<S as Serializer>::Ok, <S as Serializer>::Error>where
S: Serializer,
fn serialize<S>(
&self,
serializer: S,
) -> Result<<S as Serializer>::Ok, <S as Serializer>::Error>where
S: Serializer,
impl<T> DerefPure for Cow<'_, [T]>where
T: Clone,
no_global_oom_handling only.impl<T> DerefPure for Cow<'_, T>where
T: Clone,
impl DerefPure for Cow<'_, str>
no_global_oom_handling only.impl<B> Eq for Cow<'_, B>
Auto Trait Implementations§
impl<'a, B> Freeze for Cow<'a, B>
impl<'a, B> RefUnwindSafe for Cow<'a, B>
impl<'a, B> Send for Cow<'a, B>
impl<'a, B> Sync for Cow<'a, B>
impl<'a, B> Unpin for Cow<'a, B>
impl<'a, B> UnwindSafe for Cow<'a, B>
Blanket Implementations§
§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
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fn into_either_with<F>(self, into_left: F) -> Either<Self, Self> ⓘ
self into a Left variant of Either<Self, Self>
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fn into_bound_py_any(self, py: Python<'py>) -> Result<Bound<'py, PyAny>, PyErr>
self into an owned Python object, dropping type information.