Enum Cow

pub enum Cow<'a, B>
where
    B: 'a + ToOwned + ?Sized,
{
    Borrowed(&'a B),
    Owned(<B as ToOwned>::Owned),
}

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

Borrowed(&'a B)

Borrowed data.

Owned(<B as ToOwned>::Owned)

Owned data.

Implementations

impl<B> Cow<'_, B>

where B: ToOwned + ?Sized,

pub const fn is_borrowed(&self) -> bool

🔬This is a nightly-only experimental API. (cow_is_borrowed)

Returns true if the data is borrowed, i.e. if to_mut would require additional work.

Examples

#![feature(cow_is_borrowed)]
use std::borrow::Cow;

let cow = Cow::Borrowed("moo");
assert!(cow.is_borrowed());

let bull: Cow<'_, str> = Cow::Owned("...moo?".to_string());
assert!(!bull.is_borrowed());

pub const fn is_owned(&self) -> bool

🔬This is a nightly-only experimental API. (cow_is_borrowed)

Returns true if the data is owned, i.e. if to_mut would be a no-op.

Examples

#![feature(cow_is_borrowed)]
use std::borrow::Cow;

let cow: Cow<'_, str> = Cow::Owned("moo".to_string());
assert!(cow.is_owned());

let bull = Cow::Borrowed("...moo?");
assert!(!bull.is_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>
);

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

impl<'a> Add<&'a str> for Cow<'a, str>

type Output = Cow<'a, str>

The resulting type after applying the + operator.

fn add(self, rhs: &'a str) -> <Cow<'a, str> as Add<&'a str>>::Output

Performs the + operation.

impl<'a> Add for Cow<'a, str>

type Output = Cow<'a, str>

The resulting type after applying the + operator.

fn add(self, rhs: Cow<'a, str>) -> <Cow<'a, str> as Add>::Output

Performs the + operation.

impl<'a> AddAssign<&'a str> for Cow<'a, str>

fn add_assign(&mut self, rhs: &'a str)

Performs the += operation.

impl<'a> AddAssign for Cow<'a, str>

fn add_assign(&mut self, rhs: Cow<'a, str>)

Performs the += operation.

impl<A, B> Arbitrary for Cow<'static, B>

where A: Arbitrary + Borrow<B>, B: ToOwned<Owned = A> + Debug + ?Sized,

type Parameters = <A as Arbitrary>::Parameters

The type of parameters that arbitrary_with accepts for configuration of the generated Strategy. Parameters must implement Default.

type Strategy = Map<<A as Arbitrary>::Strategy, fn(_: A) -> Cow<'static, B>>

The type of Strategy used to generate values of type Self.

fn arbitrary_with( args: <Cow<'static, B> as Arbitrary>::Parameters, ) -> <Cow<'static, B> as Arbitrary>::Strategy

Generates a Strategy for producing arbitrary values of type the implementing type (Self). The strategy is passed the arguments given in args.

fn arbitrary() -> Self::Strategy

Generates a Strategy for producing arbitrary values of type the implementing type (Self).

impl<A, B> ArbitraryF1<A> for Cow<'static, B>

where A: Debug + Borrow<B> + 'static, B: ToOwned<Owned = A> + Debug + ?Sized,

type Parameters = ()

The type of parameters that lift1_with accepts for configuration of the lifted and generated Strategy. Parameters must implement Default.

fn lift1_with<S>( base: S, _args: <Cow<'static, B> as ArbitraryF1<A>>::Parameters, ) -> BoxedStrategy<Cow<'static, B>>

where S: Strategy<Value = A> + 'static,

Lifts a given Strategy to a new Strategy for the (presumably) bigger type. This is useful for lifting a Strategy for SomeType to a container such as Vec of SomeType. The composite strategy is passed the arguments given in args.

fn lift1<AS>(base: AS) -> BoxedStrategy<Self>

where AS: Strategy<Value = A> + 'static,

Lifts a given Strategy to a new Strategy for the (presumably) bigger type. This is useful for lifting a Strategy for SomeType to a container such as Vec<SomeType>.

impl<'a> Arg for Cow<'a, CStr>

fn as_str(&self) -> Result<&str, Errno>

Returns a view of this string as a string slice.

fn to_string_lossy(&self) -> Cow<'_, str>

Returns a potentially-lossy rendering of this string as a Cow<'_, str>.

fn as_cow_c_str(&self) -> Result<Cow<'_, CStr>, Errno>

Returns a view of this string as a maybe-owned CStr.

fn into_c_str<'b>(self) -> Result<Cow<'b, CStr>, Errno>

where Cow<'a, CStr>: 'b,

Consumes self and returns a view of this string as a maybe-owned CStr.

fn into_with_c_str<T, F>(self, f: F) -> Result<T, Errno>

where Cow<'a, CStr>: Sized, F: FnOnce(&CStr) -> Result<T, Errno>,

Runs a closure with self passed in as a &CStr.

impl<'a> Arg for Cow<'a, OsStr>

fn as_str(&self) -> Result<&str, Errno>

Returns a view of this string as a string slice.

fn to_string_lossy(&self) -> Cow<'_, str>

Returns a potentially-lossy rendering of this string as a Cow<'_, str>.

fn as_cow_c_str(&self) -> Result<Cow<'_, CStr>, Errno>

Returns a view of this string as a maybe-owned CStr.

fn into_c_str<'b>(self) -> Result<Cow<'b, CStr>, Errno>

where Cow<'a, OsStr>: 'b,

Consumes self and returns a view of this string as a maybe-owned CStr.

fn into_with_c_str<T, F>(self, f: F) -> Result<T, Errno>

where Cow<'a, OsStr>: Sized, F: FnOnce(&CStr) -> Result<T, Errno>,

Runs a closure with self passed in as a &CStr.

impl<'a> Arg for Cow<'a, str>

fn as_str(&self) -> Result<&str, Errno>

Returns a view of this string as a string slice.

fn to_string_lossy(&self) -> Cow<'_, str>

Returns a potentially-lossy rendering of this string as a Cow<'_, str>.

fn as_cow_c_str(&self) -> Result<Cow<'_, CStr>, Errno>

Returns a view of this string as a maybe-owned CStr.

fn into_c_str<'b>(self) -> Result<Cow<'b, CStr>, Errno>

where Cow<'a, str>: 'b,

Consumes self and returns a view of this string as a maybe-owned CStr.

fn into_with_c_str<T, F>(self, f: F) -> Result<T, Errno>

where Cow<'a, str>: Sized, F: FnOnce(&CStr) -> Result<T, Errno>,

Runs a closure with self passed in as a &CStr.

impl AsRef<Path> for Cow<'_, OsStr>

fn as_ref(&self) -> &Path

Converts this type into a shared reference of the (usually inferred) input type.

impl<T> AsRef<T> for Cow<'_, T>

where T: ToOwned + ?Sized,

fn as_ref(&self) -> &T

Converts this type into a shared reference of the (usually inferred) input type.

impl<'a, B> Borrow<B> for Cow<'a, B>

where B: ToOwned + ?Sized,

fn borrow(&self) -> &B

Immutably borrows from an owned value.

impl<B> Clone for Cow<'_, B>

where B: ToOwned + ?Sized,

fn clone(&self) -> Cow<'_, B>

Returns a copy of the value.

fn clone_from(&mut self, source: &Cow<'_, B>)

Performs copy-assignment from source.

impl<B> Debug for Cow<'_, B>

where B: Debug + ToOwned + ?Sized, <B as ToOwned>::Owned: Debug,

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl<B> Default for Cow<'_, B>

where B: ToOwned + ?Sized, <B as ToOwned>::Owned: Default,

fn default() -> Cow<'_, B>

Creates an owned Cow<’a, B> with the default value for the contained owned value.

impl<B> Deref for Cow<'_, B>

where B: ToOwned + ?Sized, <B as ToOwned>::Owned: Borrow<B>,

type Target = B

The resulting type after dereferencing.

fn deref(&self) -> &B

Dereferences the value.

impl<'de, 'a, T> Deserialize<'de> for Cow<'a, T>

where T: ToOwned + ?Sized, <T as ToOwned>::Owned: Deserialize<'de>,

fn deserialize<D>( deserializer: D, ) -> Result<Cow<'a, T>, <D as Deserializer<'de>>::Error>

where D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl<B> Display for Cow<'_, B>

where B: Display + ToOwned + ?Sized, <B as ToOwned>::Owned: Display,

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl<T> EncodeAsVarULE<T> for Cow<'_, T>

where T: VarULE + ToOwned + ?Sized,

fn encode_var_ule_as_slices<R>(&self, cb: impl FnOnce(&[&[u8]]) -> R) -> R

Calls cb with a piecewise list of byte slices that when concatenated produce the memory pattern of the corresponding instance of T.

fn encode_var_ule_len(&self) -> usize

Return the length, in bytes, of the corresponding VarULE type

fn encode_var_ule_write(&self, dst: &mut [u8])

Write the corresponding VarULE type to the dst buffer. dst should be the size of Self::encode_var_ule_len()

impl<'a> Extend<Cow<'a, OsStr>> for OsString

fn extend<T>(&mut self, iter: T)

where T: IntoIterator<Item = Cow<'a, OsStr>>,

Extends a collection with the contents of an iterator.

fn extend_one(&mut self, item: A)

🔬This is a nightly-only experimental API. (extend_one)

Extends a collection with exactly one element.

fn extend_reserve(&mut self, additional: usize)

🔬This is a nightly-only experimental API. (extend_one)

Reserves capacity in a collection for the given number of additional elements.

impl<'a> Extend<Cow<'a, str>> for String

fn extend<I>(&mut self, iter: I)

where I: IntoIterator<Item = Cow<'a, str>>,

Extends a collection with the contents of an iterator.

fn extend_one(&mut self, s: Cow<'a, str>)

🔬This is a nightly-only experimental API. (extend_one)

Extends a collection with exactly one element.

fn extend_reserve(&mut self, additional: usize)

🔬This is a nightly-only experimental API. (extend_one)

Reserves capacity in a collection for the given number of additional elements.

impl<'a, T> From<&'a [T]> for Cow<'a, [T]>

where T: Clone,

fn from(s: &'a [T]) -> Cow<'a, [T]>

Creates a Borrowed variant of Cow from a slice.

This conversion does not allocate or clone the data.

impl<'a, T, const N: usize> From<&'a [T; N]> for Cow<'a, [T]>

where T: Clone,

fn from(s: &'a [T; N]) -> Cow<'a, [T]>

Creates a Borrowed variant of Cow from a reference to an array.

This conversion does not allocate or clone the data.

impl<'a> From<&'a BStr> for Cow<'a, BStr>

fn from(s: &'a BStr) -> Cow<'a, BStr>

Converts to this type from the input type.

impl<'a> From<&'a BString> for Cow<'a, BStr>

fn from(s: &'a BString) -> Cow<'a, BStr>

Converts to this type from the input type.

impl<'a> From<&'a CStr> for Cow<'a, CStr>

fn from(s: &'a CStr) -> Cow<'a, CStr>

Converts a CStr into a borrowed Cow without copying or allocating.

impl<'a> From<&'a CString> for Cow<'a, CStr>

fn from(s: &'a CString) -> Cow<'a, CStr>

Converts a &CString into a borrowed Cow without copying or allocating.

impl<'a> From<&'a OsStr> for Cow<'a, OsStr>

fn from(s: &'a OsStr) -> Cow<'a, OsStr>

Converts the string reference into a Cow::Borrowed.

impl<'a> From<&'a OsString> for Cow<'a, OsStr>

fn from(s: &'a OsString) -> Cow<'a, OsStr>

Converts the string reference into a Cow::Borrowed.

impl<'a> From<&'a Path> for Cow<'a, Path>

fn from(s: &'a Path) -> Cow<'a, Path>

Creates a clone-on-write pointer from a reference to Path.

This conversion does not clone or allocate.

impl<'a> From<&'a PathBuf> for Cow<'a, Path>

fn from(p: &'a PathBuf) -> Cow<'a, Path>

Creates a clone-on-write pointer from a reference to PathBuf.

This conversion does not clone or allocate.

impl<'a> From<&'a String> for Cow<'a, str>

fn from(s: &'a String) -> Cow<'a, str>

Converts a String reference into a Borrowed variant. No heap allocation is performed, and the string is not copied.

Example

let s = "eggplant".to_string();
assert_eq!(Cow::from(&s), Cow::Borrowed("eggplant"));

impl<'a, T> From<&'a Vec<T>> for Cow<'a, [T]>

where T: Clone,

fn from(v: &'a Vec<T>) -> Cow<'a, [T]>

Creates a Borrowed variant of Cow from a reference to Vec.

This conversion does not allocate or clone the data.

impl<'a> From<&'a str> for Cow<'a, str>

fn from(s: &'a str) -> Cow<'a, str>

Converts a string slice into a Borrowed variant. No heap allocation is performed, and the string is not copied.

Example

assert_eq!(Cow::from("eggplant"), Cow::Borrowed("eggplant"));

impl<'a> From<BString> for Cow<'a, BStr>

fn from(s: BString) -> Cow<'a, BStr>

Converts to this type from the input type.

impl<'a> From<CString> for Cow<'a, CStr>

fn from(s: CString) -> Cow<'a, CStr>

Converts a CString into an owned Cow without copying or allocating.

impl<T> From<Cow<'_, [T]>> for Box<[T]>

where T: Clone,

fn from(cow: Cow<'_, [T]>) -> Box<[T]>

Converts a Cow<'_, [T]> into a Box<[T]>

When cow is the Cow::Borrowed variant, this conversion allocates on the heap and copies the underlying slice. Otherwise, it will try to reuse the owned Vec’s allocation.

impl From<Cow<'_, CStr>> for Box<CStr>

fn from(cow: Cow<'_, CStr>) -> Box<CStr>

Converts a Cow<'a, CStr> into a Box<CStr>, by copying the contents if they are borrowed.

impl From<Cow<'_, OsStr>> for Box<OsStr>

fn from(cow: Cow<'_, OsStr>) -> Box<OsStr>

Converts a Cow<'a, OsStr> into a Box<OsStr>, by copying the contents if they are borrowed.

impl From<Cow<'_, Path>> for Box<Path>

fn from(cow: Cow<'_, Path>) -> Box<Path>

Creates a boxed Path from a clone-on-write pointer.

Converting from a Cow::Owned does not clone or allocate.

impl From<Cow<'_, str>> for 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}");

impl<'a, T> From<Cow<'a, [T]>> for Vec<T>

where [T]: ToOwned<Owned = 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));

impl<'a, B> From<Cow<'a, B>> for Arc<B>

where B: ToOwned + ?Sized, Arc<B>: From<&'a B> + From<<B as ToOwned>::Owned>,

fn from(cow: Cow<'a, B>) -> Arc<B>

Creates an atomically reference-counted pointer from a clone-on-write pointer by copying its content.

Example

let cow: Cow<'_, str> = Cow::Borrowed("eggplant");
let shared: Arc<str> = Arc::from(cow);
assert_eq!("eggplant", &shared[..]);

impl<'a, B> From<Cow<'a, B>> for Rc<B>

where B: ToOwned + ?Sized, Rc<B>: From<&'a B> + From<<B as ToOwned>::Owned>,

fn from(cow: Cow<'a, B>) -> Rc<B>

Creates a reference-counted pointer from a clone-on-write pointer by copying its content.

Example

let cow: Cow<'_, str> = Cow::Borrowed("eggplant");
let shared: Rc<str> = Rc::from(cow);
assert_eq!("eggplant", &shared[..]);

impl<'a> From<Cow<'a, CStr>> for CString

fn from(s: Cow<'a, CStr>) -> CString

Converts a Cow<'a, CStr> into a CString, by copying the contents if they are borrowed.

impl<'a> From<Cow<'a, OsStr>> for OsString

fn from(s: Cow<'a, OsStr>) -> OsString

Converts a Cow<'a, OsStr> into an OsString, by copying the contents if they are borrowed.

impl<'a> From<Cow<'a, Path>> for PathBuf

fn from(p: Cow<'a, Path>) -> PathBuf

Converts a clone-on-write pointer to an owned path.

Converting from a Cow::Owned does not clone or allocate.

impl<'a> From<Cow<'a, str>> for 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");

impl<'a> From<Cow<'a, str>> for 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();

impl<'a, 'b> From<Cow<'b, str>> for Box<dyn Error + 'a>

fn from(err: Cow<'b, str>) -> Box<dyn Error + 'a>

Converts a Cow into a box of dyn Error.

Examples

use std::error::Error;
use std::mem;
use std::borrow::Cow;

let a_cow_str_error = Cow::from("a str error");
let a_boxed_error = Box::<dyn Error>::from(a_cow_str_error);
assert!(mem::size_of::<Box<dyn Error>>() == mem::size_of_val(&a_boxed_error))

impl<'a, 'b> From<Cow<'b, str>> for Box<dyn Error + Send + Sync + 'a>

fn from(err: Cow<'b, str>) -> Box<dyn Error + Send + Sync + 'a>

Converts a Cow into a box of dyn Error + Send + Sync.

Examples

use std::error::Error;
use std::mem;
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!(
    mem::size_of::<Box<dyn Error + Send + Sync>>() == mem::size_of_val(&a_boxed_error))

impl From<Cow<'static, [u8]>> for Body

fn from(buf: Cow<'static, [u8]>) -> Body

Converts to this type from the input type.

impl<D, B> From<Cow<'static, B>> for Full<D>

where D: Buf + From<&'static B> + From<<B as ToOwned>::Owned>, B: ToOwned + ?Sized,

fn from(cow: Cow<'static, B>) -> Full<D>

Converts to this type from the input type.

impl From<Cow<'static, str>> for Body

fn from(buf: Cow<'static, str>) -> Body

Converts to this type from the input type.

impl<'key> From<Key<'key>> for Cow<'static, str>

fn from(key: Key<'key>) -> Cow<'static, str>

Converts to this type from the input type.

impl<'a> From<OsString> for Cow<'a, OsStr>

fn from(s: OsString) -> Cow<'a, OsStr>

Moves the string into a Cow::Owned.

impl<'a> From<PathBuf> for Cow<'a, Path>

fn from(s: PathBuf) -> Cow<'a, Path>

Creates a clone-on-write pointer from an owned instance of PathBuf.

This conversion does not clone or allocate.

impl<'a> From<PercentDecode<'a>> for Cow<'a, [u8]>

fn from(iter: PercentDecode<'a>) -> Cow<'a, [u8]>

Converts to this type from the input type.

impl<'a> From<PercentEncode<'a>> for Cow<'a, str>

fn from(iter: PercentEncode<'a>) -> Cow<'a, str>

Converts to this type from the input type.

impl<'a> From<String> for Cow<'a, str>

fn from(s: String) -> Cow<'a, str>

Converts a String into an Owned variant. No heap allocation is performed, and the string is not copied.

Example

let s = "eggplant".to_string();
let s2 = "eggplant".to_string();
assert_eq!(Cow::from(s), Cow::<'static, str>::Owned(s2));

impl<'a, T> From<Vec<T>> for Cow<'a, [T]>

where T: Clone,

fn from(v: Vec<T>) -> Cow<'a, [T]>

Creates an Owned variant of Cow from an owned instance of Vec.

This conversion does not allocate or clone the data.

impl<'a, 'b> FromIterator<&'b str> for Cow<'a, str>

fn from_iter<I>(it: I) -> Cow<'a, str>

where I: IntoIterator<Item = &'b str>,

Creates a value from an iterator.

impl<'a> FromIterator<Cow<'a, OsStr>> for OsString

fn from_iter<I>(iter: I) -> OsString

where I: IntoIterator<Item = Cow<'a, OsStr>>,

Creates a value from an iterator.

impl<'a> FromIterator<Cow<'a, str>> for Box<str>

fn from_iter<T>(iter: T) -> Box<str>

where T: IntoIterator<Item = Cow<'a, str>>,

Creates a value from an iterator.

impl<'a> FromIterator<Cow<'a, str>> for String

fn from_iter<I>(iter: I) -> String

where I: IntoIterator<Item = Cow<'a, str>>,

Creates a value from an iterator.

impl<'a> FromIterator<String> for Cow<'a, str>

fn from_iter<I>(it: I) -> Cow<'a, str>

where I: IntoIterator<Item = String>,

Creates a value from an iterator.

impl<'a, T> FromIterator<T> for Cow<'a, [T]>

where T: Clone,

fn from_iter<I>(it: I) -> Cow<'a, [T]>

where I: IntoIterator<Item = T>,

Creates a value from an iterator.

impl<'a> FromIterator<char> for Cow<'a, str>

fn from_iter<I>(it: I) -> Cow<'a, str>

where I: IntoIterator<Item = char>,

Creates a value from an iterator.

impl<'a> FromParallelIterator<Cow<'a, OsStr>> for OsString

Collects OS-string slices from a parallel iterator into an OS-string.

fn from_par_iter<I>(par_iter: I) -> OsString

where I: IntoParallelIterator<Item = Cow<'a, OsStr>>,

Creates an instance of the collection from the parallel iterator par_iter.

impl<'a> FromParallelIterator<Cow<'a, str>> for String

Collects string slices from a parallel iterator into a string.

fn from_par_iter<I>(par_iter: I) -> String

where I: IntoParallelIterator<Item = Cow<'a, str>>,

Creates an instance of the collection from the parallel iterator par_iter.

impl<'a, C, T> FromParallelIterator<T> for Cow<'a, C>

where C: ToOwned + ?Sized, <C as ToOwned>::Owned: FromParallelIterator<T>, T: Send,

Collects an arbitrary Cow collection.

Note, the standard library only has FromIterator for Cow<'a, str> and Cow<'a, [T]>, because no one thought to add a blanket implementation before it was stabilized.

fn from_par_iter<I>(par_iter: I) -> Cow<'a, C>

where I: IntoParallelIterator<Item = T>,

Creates an instance of the collection from the parallel iterator par_iter.

impl<B> Hash for Cow<'_, B>

where B: Hash + ToOwned + ?Sized,

fn hash<H>(&self, state: &mut H)

where H: Hasher,

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl<T> IdentFragment for Cow<'_, T>

where T: IdentFragment + ToOwned + ?Sized,

fn span(&self) -> Option<Span>

Span associated with this IdentFragment.

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Format this value as an identifier fragment.

impl<'de, 'a, E> IntoDeserializer<'de, E> for Cow<'a, str>

where E: Error,

type Deserializer = CowStrDeserializer<'a, E>

The type of the deserializer being converted into.

fn into_deserializer(self) -> CowStrDeserializer<'a, E>

Convert this value into a deserializer.

impl IntoResponse for Cow<'static, [u8]>

fn into_response(self) -> Response<Body>

Create a response.

impl IntoResponse for Cow<'static, str>

fn into_response(self) -> Response<Body>

Create a response.

impl<B> Ord for Cow<'_, B>

where B: Ord + ToOwned + ?Sized,

fn cmp(&self, other: &Cow<'_, B>) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl<'a> ParallelExtend<Cow<'a, OsStr>> for OsString

Extends an OS-string with string slices from a parallel iterator.

fn par_extend<I>(&mut self, par_iter: I)

where I: IntoParallelIterator<Item = Cow<'a, OsStr>>,

Extends an instance of the collection with the elements drawn from the parallel iterator par_iter.

impl<'a> ParallelExtend<Cow<'a, str>> for String

Extends a string with string slices from a parallel iterator.

fn par_extend<I>(&mut self, par_iter: I)

where I: IntoParallelIterator<Item = Cow<'a, str>>,

Extends an instance of the collection with the elements drawn from the parallel iterator par_iter.

impl<T, U> PartialEq<&[U]> for Cow<'_, [T]>

where T: PartialEq<U> + Clone,

fn eq(&self, other: &&[U]) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &&[U]) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a, 'b> PartialEq<&'a BStr> for Cow<'a, [u8]>

fn eq(&self, other: &&'a BStr) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a, 'b> PartialEq<&'a BStr> for Cow<'a, BStr>

fn eq(&self, other: &&'a BStr) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a, 'b> PartialEq<&'a BStr> for Cow<'a, str>

fn eq(&self, other: &&'a BStr) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a, 'b> PartialEq<&'b OsStr> for Cow<'a, OsStr>

fn eq(&self, other: &&'b OsStr) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a, 'b> PartialEq<&'b OsStr> for Cow<'a, Path>

fn eq(&self, other: &&'b OsStr) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a, 'b> PartialEq<&'b Path> for Cow<'a, Path>

fn eq(&self, other: &&'b Path) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a, 'b> PartialEq<&'a Path> for Cow<'b, OsStr>

fn eq(&self, other: &&'a Path) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<T, U> PartialEq<&mut [U]> for Cow<'_, [T]>

where T: PartialEq<U> + Clone,

fn eq(&self, other: &&mut [U]) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &&mut [U]) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a, 'b> PartialEq<&'b str> for Cow<'a, str>

fn eq(&self, other: &&'b str) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &&'b str) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a, 'b> PartialEq<Cow<'a, [u8]>> for &'a BStr

fn eq(&self, other: &Cow<'a, [u8]>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a, 'b> PartialEq<Cow<'a, BStr>> for &'a BStr

fn eq(&self, other: &Cow<'a, BStr>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a, 'b> PartialEq<Cow<'a, OsStr>> for &'b OsStr

fn eq(&self, other: &Cow<'a, OsStr>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a, 'b> PartialEq<Cow<'a, OsStr>> for OsStr

fn eq(&self, other: &Cow<'a, OsStr>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a, 'b> PartialEq<Cow<'a, OsStr>> for OsString

fn eq(&self, other: &Cow<'a, OsStr>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a> PartialEq<Cow<'a, OsStr>> for Path

fn eq(&self, other: &Cow<'a, OsStr>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a> PartialEq<Cow<'a, OsStr>> for PathBuf

fn eq(&self, other: &Cow<'a, OsStr>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a, 'b> PartialEq<Cow<'a, Path>> for &'b OsStr

fn eq(&self, other: &Cow<'a, Path>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a, 'b> PartialEq<Cow<'a, Path>> for &'b Path

fn eq(&self, other: &Cow<'a, Path>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a> PartialEq<Cow<'a, Path>> for OsStr

fn eq(&self, other: &Cow<'a, Path>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a> PartialEq<Cow<'a, Path>> for OsString

fn eq(&self, other: &Cow<'a, Path>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a> PartialEq<Cow<'a, Path>> for Path

fn eq(&self, other: &Cow<'a, Path>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a> PartialEq<Cow<'a, Path>> for PathBuf

fn eq(&self, other: &Cow<'a, Path>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a, 'b> PartialEq<Cow<'a, str>> for &'a BStr

fn eq(&self, other: &Cow<'a, str>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a, 'b> PartialEq<Cow<'a, str>> for &'b str

fn eq(&self, other: &Cow<'a, str>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Cow<'a, str>) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a, 'b> PartialEq<Cow<'a, str>> for String

fn eq(&self, other: &Cow<'a, str>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Cow<'a, str>) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a, 'b> PartialEq<Cow<'a, str>> for str

fn eq(&self, other: &Cow<'a, str>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Cow<'a, str>) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a, 'b, B, C> PartialEq<Cow<'b, C>> for Cow<'a, B>

where B: PartialEq<C> + ToOwned + ?Sized, C: ToOwned + ?Sized,

fn eq(&self, other: &Cow<'b, C>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a, 'b> PartialEq<Cow<'b, OsStr>> for &'a Path

fn eq(&self, other: &Cow<'b, OsStr>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a, 'b> PartialEq<OsStr> for Cow<'a, OsStr>

fn eq(&self, other: &OsStr) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a> PartialEq<OsStr> for Cow<'a, Path>

fn eq(&self, other: &OsStr) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a, 'b> PartialEq<OsString> for Cow<'a, OsStr>

fn eq(&self, other: &OsString) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a> PartialEq<OsString> for Cow<'a, Path>

fn eq(&self, other: &OsString) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a> PartialEq<Path> for Cow<'a, OsStr>

fn eq(&self, other: &Path) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a> PartialEq<Path> for Cow<'a, Path>

fn eq(&self, other: &Path) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a> PartialEq<PathBuf> for Cow<'a, OsStr>

fn eq(&self, other: &PathBuf) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a> PartialEq<PathBuf> for Cow<'a, Path>

fn eq(&self, other: &PathBuf) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a, 'b> PartialEq<String> for Cow<'a, str>

fn eq(&self, other: &String) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &String) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<T, U, A> PartialEq<Vec<U, A>> for Cow<'_, [T]>

where A: Allocator, T: PartialEq<U> + Clone,

fn eq(&self, other: &Vec<U, A>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Vec<U, A>) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a, 'b> PartialEq<str> for Cow<'a, str>

fn eq(&self, other: &str) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &str) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a, 'b> PartialOrd<&'b OsStr> for Cow<'a, OsStr>

fn partial_cmp(&self, other: &&'b OsStr) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<'a, 'b> PartialOrd<&'b OsStr> for Cow<'a, Path>

fn partial_cmp(&self, other: &&'b OsStr) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<'a, 'b> PartialOrd<&'b Path> for Cow<'a, Path>

fn partial_cmp(&self, other: &&'b Path) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<'a, 'b> PartialOrd<&'a Path> for Cow<'b, OsStr>

fn partial_cmp(&self, other: &&'a Path) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<'a, 'b> PartialOrd<Cow<'a, OsStr>> for &'b OsStr

fn partial_cmp(&self, other: &Cow<'a, OsStr>) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<'a, 'b> PartialOrd<Cow<'a, OsStr>> for OsStr

fn partial_cmp(&self, other: &Cow<'a, OsStr>) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<'a, 'b> PartialOrd<Cow<'a, OsStr>> for OsString

fn partial_cmp(&self, other: &Cow<'a, OsStr>) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<'a> PartialOrd<Cow<'a, OsStr>> for Path

fn partial_cmp(&self, other: &Cow<'a, OsStr>) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<'a> PartialOrd<Cow<'a, OsStr>> for PathBuf

fn partial_cmp(&self, other: &Cow<'a, OsStr>) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<'a, 'b> PartialOrd<Cow<'a, Path>> for &'b OsStr

fn partial_cmp(&self, other: &Cow<'a, Path>) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<'a, 'b> PartialOrd<Cow<'a, Path>> for &'b Path

fn partial_cmp(&self, other: &Cow<'a, Path>) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<'a> PartialOrd<Cow<'a, Path>> for OsStr

fn partial_cmp(&self, other: &Cow<'a, Path>) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<'a> PartialOrd<Cow<'a, Path>> for OsString

fn partial_cmp(&self, other: &Cow<'a, Path>) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<'a> PartialOrd<Cow<'a, Path>> for Path

fn partial_cmp(&self, other: &Cow<'a, Path>) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<'a> PartialOrd<Cow<'a, Path>> for PathBuf

fn partial_cmp(&self, other: &Cow<'a, Path>) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<'a, 'b> PartialOrd<Cow<'b, OsStr>> for &'a Path

fn partial_cmp(&self, other: &Cow<'b, OsStr>) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<'a, 'b> PartialOrd<OsStr> for Cow<'a, OsStr>

fn partial_cmp(&self, other: &OsStr) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<'a> PartialOrd<OsStr> for Cow<'a, Path>

fn partial_cmp(&self, other: &OsStr) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<'a, 'b> PartialOrd<OsString> for Cow<'a, OsStr>

fn partial_cmp(&self, other: &OsString) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<'a> PartialOrd<OsString> for Cow<'a, Path>

fn partial_cmp(&self, other: &OsString) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<'a> PartialOrd<Path> for Cow<'a, OsStr>

fn partial_cmp(&self, other: &Path) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<'a> PartialOrd<Path> for Cow<'a, Path>

fn partial_cmp(&self, other: &Path) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<'a> PartialOrd<PathBuf> for Cow<'a, OsStr>

fn partial_cmp(&self, other: &PathBuf) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<'a> PartialOrd<PathBuf> for Cow<'a, Path>

fn partial_cmp(&self, other: &PathBuf) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<'a, B> PartialOrd for Cow<'a, B>

where B: PartialOrd + ToOwned + ?Sized,

fn partial_cmp(&self, other: &Cow<'a, B>) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<'a> Replacer for &'a Cow<'a, [u8]>

fn replace_append(&mut self, caps: &Captures<'_>, dst: &mut Vec<u8>)

Appends possibly empty data to dst to replace the current match.

fn no_expansion(&mut self) -> Option<Cow<'_, [u8]>>

Return a fixed unchanging replacement byte string.

fn by_ref<'r>(&'r mut self) -> ReplacerRef<'r, Self>

Returns a type that implements Replacer, but that borrows and wraps this Replacer.

impl<'a> Replacer for &'a Cow<'a, str>

fn replace_append(&mut self, caps: &Captures<'_>, dst: &mut String)

Appends possibly empty data to dst to replace the current match.

fn no_expansion(&mut self) -> Option<Cow<'_, str>>

Return a fixed unchanging replacement string.

fn by_ref<'r>(&'r mut self) -> ReplacerRef<'r, Self>

Returns a type that implements Replacer, but that borrows and wraps this Replacer.

impl<'a> Replacer for Cow<'a, [u8]>

fn replace_append(&mut self, caps: &Captures<'_>, dst: &mut Vec<u8>)

Appends possibly empty data to dst to replace the current match.

fn no_expansion(&mut self) -> Option<Cow<'_, [u8]>>

Return a fixed unchanging replacement byte string.

fn by_ref<'r>(&'r mut self) -> ReplacerRef<'r, Self>

Returns a type that implements Replacer, but that borrows and wraps this Replacer.

impl<'a> Replacer for Cow<'a, str>

fn replace_append(&mut self, caps: &Captures<'_>, dst: &mut String)

Appends possibly empty data to dst to replace the current match.

fn no_expansion(&mut self) -> Option<Cow<'_, str>>

Return a fixed unchanging replacement string.

fn by_ref<'r>(&'r mut self) -> ReplacerRef<'r, Self>

Returns a type that implements Replacer, but that borrows and wraps this Replacer.

impl<'a, T> Serialize for Cow<'a, T>

where T: Serialize + ToOwned + ?Sized,

fn serialize<S>( &self, serializer: S, ) -> Result<<S as Serializer>::Ok, <S as Serializer>::Error>

where S: Serializer,

Serialize this value into the given Serde serializer.

impl<T> ToTokens for Cow<'_, T>

where T: ToTokens + ToOwned + ?Sized,

fn to_tokens(&self, tokens: &mut TokenStream)

🔬This is a nightly-only experimental API. (proc_macro_totokens)

Write self to the given TokenStream.

fn to_token_stream(&self) -> TokenStream

🔬This is a nightly-only experimental API. (proc_macro_totokens)

Convert self directly into a TokenStream object.

fn into_token_stream(self) -> TokenStream

where Self: Sized,

🔬This is a nightly-only experimental API. (proc_macro_totokens)

Convert self directly into a TokenStream object.

impl<'a, T> ToTokens for Cow<'a, T>

where T: ToOwned + ToTokens + ?Sized,

fn to_tokens(&self, tokens: &mut TokenStream)

Write self to the given TokenStream.

fn to_token_stream(&self) -> TokenStream

Convert self directly into a TokenStream object.

fn into_token_stream(self) -> TokenStream

where Self: Sized,

Convert self directly into a TokenStream object.

impl<'a, T> Writeable for Cow<'a, T>

where T: Writeable + ToOwned + ?Sized,

fn write_to<W>(&self, sink: &mut W) -> Result<(), Error>

where W: Write + ?Sized,

Writes a string to the given sink. Errors from the sink are bubbled up. The default implementation delegates to write_to_parts, and discards any Part annotations.

fn write_to_parts<W>(&self, sink: &mut W) -> Result<(), Error>

where W: PartsWrite + ?Sized,

Write bytes and Part annotations to the given sink. Errors from the sink are bubbled up. The default implementation delegates to write_to, and doesn’t produce any Part annotations.

fn writeable_length_hint(&self) -> LengthHint

Returns a hint for the number of UTF-8 bytes that will be written to the sink.

fn write_to_string(&self) -> Cow<'_, str>

Creates a new String with the data from this Writeable. Like ToString, but smaller and faster.

fn writeable_cmp_bytes(&self, other: &[u8]) -> Ordering

Compares the contents of this Writeable to the given bytes without allocating a String to hold the Writeable contents.

impl<'a, T> Yokeable<'a> for Cow<'static, T>

where T: 'static + ToOwned + ?Sized, <T as ToOwned>::Owned: Sized,

type Output = Cow<'a, T>

This type MUST be Self with the 'static replaced with 'a, i.e. Self<'a>

fn transform(&'a self) -> &'a Cow<'a, T>

This method must cast self between &'a Self<'static> and &'a Self<'a>.

fn transform_owned(self) -> Cow<'a, T>

This method must cast self between Self<'static> and Self<'a>.

unsafe fn make(from: Cow<'a, T>) -> Cow<'static, T>

This method can be used to cast away Self<'a>’s lifetime.

fn transform_mut<F>(&'a mut self, f: F)

where F: 'static + for<'b> FnOnce(&'b mut <Cow<'static, T> as Yokeable<'a>>::Output),

This method must cast self between &'a mut Self<'static> and &'a mut Self<'a>, and pass it to f.

impl<'zf, B> ZeroFrom<'zf, Cow<'_, B>> for Cow<'zf, B>

where B: ToOwned + ?Sized,

fn zero_from(other: &'zf Cow<'_, B>) -> Cow<'zf, B>

Clone the other C into a struct that may retain references into C.

impl<'zf> ZeroFrom<'zf, String> for Cow<'zf, str>

fn zero_from(other: &'zf String) -> Cow<'zf, str>

Clone the other C into a struct that may retain references into C.

impl<'zf> ZeroFrom<'zf, str> for Cow<'zf, str>

fn zero_from(other: &'zf str) -> Cow<'zf, str>

Clone the other C into a struct that may retain references into C.

impl<B> DerefPure for Cow<'_, B>

where B: ToOwned + ?Sized, <B as ToOwned>::Owned: Borrow<B>,

impl<B> Eq for Cow<'_, B>

where B: Eq + ToOwned + ?Sized,