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§
source§impl<B> Cow<'_, B>
impl<B> Cow<'_, B>
const: unstable · sourcepub fn is_borrowed(&self) -> bool
🔬This is a nightly-only experimental API. (cow_is_borrowed
)
pub fn is_borrowed(&self) -> bool
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());
const: unstable · sourcepub fn is_owned(&self) -> bool
🔬This is a nightly-only experimental API. (cow_is_borrowed
)
pub fn is_owned(&self) -> bool
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());
1.0.0 · sourcepub 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>
);
1.0.0 · sourcepub 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 · source§impl<'a> AddAssign<&'a str> for Cow<'a, str>
impl<'a> AddAssign<&'a str> for Cow<'a, str>
source§fn add_assign(&mut self, rhs: &'a str)
fn add_assign(&mut self, rhs: &'a str)
+=
operation. Read moresource§impl<'a> Arg for Cow<'a, CStr>
impl<'a> Arg for Cow<'a, CStr>
source§fn to_string_lossy(&self) -> Cow<'_, str>
fn to_string_lossy(&self) -> Cow<'_, str>
Cow<'_, str>
.source§fn as_cow_c_str(&self) -> Result<Cow<'_, CStr>, Errno>
fn as_cow_c_str(&self) -> Result<Cow<'_, CStr>, Errno>
CStr
.source§impl<'a> Arg for Cow<'a, OsStr>
impl<'a> Arg for Cow<'a, OsStr>
source§fn to_string_lossy(&self) -> Cow<'_, str>
fn to_string_lossy(&self) -> Cow<'_, str>
Cow<'_, str>
.source§fn as_cow_c_str(&self) -> Result<Cow<'_, CStr>, Errno>
fn as_cow_c_str(&self) -> Result<Cow<'_, CStr>, Errno>
CStr
.source§impl<'a> Arg for Cow<'a, str>
impl<'a> Arg for Cow<'a, str>
source§fn to_string_lossy(&self) -> Cow<'_, str>
fn to_string_lossy(&self) -> Cow<'_, str>
Cow<'_, str>
.source§fn as_cow_c_str(&self) -> Result<Cow<'_, CStr>, Errno>
fn as_cow_c_str(&self) -> Result<Cow<'_, CStr>, Errno>
CStr
.source§impl<'de, 'a, T> Deserialize<'de> for Cow<'a, T>
impl<'de, 'a, T> Deserialize<'de> for Cow<'a, T>
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>,
1.19.0 · source§impl<'a> Extend<Cow<'a, str>> for String
impl<'a> Extend<Cow<'a, str>> for String
source§fn extend<I>(&mut self, iter: I)
fn extend<I>(&mut self, iter: I)
source§fn extend_one(&mut self, s: Cow<'a, str>)
fn extend_one(&mut self, s: Cow<'a, str>)
extend_one
)source§fn extend_reserve(&mut self, additional: usize)
fn extend_reserve(&mut self, additional: usize)
extend_one
)source§impl<'a> From<&'a Rope> for Cow<'a, str>
impl<'a> From<&'a Rope> for Cow<'a, str>
Attempts to borrow the contents of the Rope
, but will convert to an
owned string if the contents is not contiguous in memory.
Runs in best case O(1), worst case O(N).
1.45.0 · source§impl From<Cow<'_, str>> for Box<str>
impl From<Cow<'_, str>> for Box<str>
source§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 · source§impl<'a, T> From<Cow<'a, [T]>> for Vec<T>
impl<'a, T> From<Cow<'a, [T]>> for Vec<T>
source§fn from(s: Cow<'a, [T]>) -> Vec<T>
fn from(s: Cow<'a, [T]>) -> Vec<T>
Convert 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 · source§impl<'a> From<Cow<'a, str>> for String
impl<'a> From<Cow<'a, str>> for String
source§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");
1.22.0 · source§impl<'a, 'b> From<Cow<'b, str>> for Box<dyn Error + 'a>
impl<'a, 'b> From<Cow<'b, str>> for Box<dyn Error + 'a>
1.22.0 · source§impl<'a, 'b> From<Cow<'b, str>> for Box<dyn Error + Sync + Send + 'a>
impl<'a, 'b> From<Cow<'b, str>> for Box<dyn Error + Sync + Send + 'a>
source§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::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))
source§impl<'a> From<RopeSlice<'a>> for Cow<'a, str>
impl<'a> From<RopeSlice<'a>> for Cow<'a, str>
Attempts to borrow the contents of the slice, but will convert to an owned string if the contents is not contiguous in memory.
Runs in best case O(1), worst case O(N).
source§impl<'a> FromParallelIterator<Cow<'a, str>> for String
impl<'a> FromParallelIterator<Cow<'a, str>> for String
Collects string slices from a parallel iterator into a string.
source§fn from_par_iter<I>(par_iter: I) -> String
fn from_par_iter<I>(par_iter: I) -> String
par_iter
. Read moresource§impl<'a, C, T> FromParallelIterator<T> for Cow<'a, C>
impl<'a, C, T> FromParallelIterator<T> for Cow<'a, C>
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.
source§fn from_par_iter<I>(par_iter: I) -> Cow<'a, C>where
I: IntoParallelIterator<Item = T>,
fn from_par_iter<I>(par_iter: I) -> Cow<'a, C>where
I: IntoParallelIterator<Item = T>,
par_iter
. Read moresource§impl<T> IdentFragment for Cow<'_, T>
impl<T> IdentFragment for Cow<'_, T>
source§impl<'de, 'a, E> IntoDeserializer<'de, E> for Cow<'a, str>where
E: Error,
impl<'de, 'a, E> IntoDeserializer<'de, E> for Cow<'a, str>where
E: Error,
§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>
1.0.0 · source§impl<B> Ord for Cow<'_, B>
impl<B> Ord for Cow<'_, B>
1.21.0 · source§fn max(self, other: Self) -> Selfwhere
Self: Sized,
fn max(self, other: Self) -> Selfwhere
Self: Sized,
source§impl<'a> ParallelExtend<Cow<'a, str>> for String
impl<'a> ParallelExtend<Cow<'a, str>> for String
Extends a string with string slices from a parallel iterator.
source§fn par_extend<I>(&mut self, par_iter: I)
fn par_extend<I>(&mut self, par_iter: I)
par_iter
. Read moresource§impl<'a, 'b> PartialEq<&'a BStr> for Cow<'a, [u8]>
impl<'a, 'b> PartialEq<&'a BStr> for Cow<'a, [u8]>
source§impl<'a, 'b> PartialEq<&'a BStr> for Cow<'a, BStr>
impl<'a, 'b> PartialEq<&'a BStr> for Cow<'a, BStr>
source§impl<'a, 'b> PartialEq<&'a BStr> for Cow<'a, str>
impl<'a, 'b> PartialEq<&'a BStr> for Cow<'a, str>
1.8.0 · source§impl<'a, 'b> PartialEq<&'b OsStr> for Cow<'a, OsStr>
impl<'a, 'b> PartialEq<&'b OsStr> for Cow<'a, OsStr>
1.8.0 · source§impl<'a, 'b> PartialEq<&'b OsStr> for Cow<'a, Path>
impl<'a, 'b> PartialEq<&'b OsStr> for Cow<'a, Path>
1.6.0 · source§impl<'a, 'b> PartialEq<&'b Path> for Cow<'a, Path>
impl<'a, 'b> PartialEq<&'b Path> for Cow<'a, Path>
1.8.0 · source§impl<'a, 'b> PartialEq<&'a Path> for Cow<'b, OsStr>
impl<'a, 'b> PartialEq<&'a Path> for Cow<'b, OsStr>
source§impl<'a, 'b> PartialEq<&'b Utf8Path> for Cow<'a, Utf8Path>
impl<'a, 'b> PartialEq<&'b Utf8Path> for Cow<'a, Utf8Path>
source§impl<'a, 'b> PartialEq<&'a Utf8Path> for Cow<'b, OsStr>
impl<'a, 'b> PartialEq<&'a Utf8Path> for Cow<'b, OsStr>
source§impl<'a, 'b> PartialEq<&'a Utf8Path> for Cow<'b, Path>
impl<'a, 'b> PartialEq<&'a Utf8Path> for Cow<'b, Path>
source§impl<'a, 'b> PartialEq<&'a Utf8Path> for Cow<'b, str>
impl<'a, 'b> PartialEq<&'a Utf8Path> for Cow<'b, str>
1.0.0 · source§impl<T, U> PartialEq<&mut [U]> for Cow<'_, [T]>
impl<T, U> PartialEq<&mut [U]> for Cow<'_, [T]>
1.8.0 · source§impl<'a, 'b> PartialEq<Cow<'a, OsStr>> for &'b OsStr
impl<'a, 'b> PartialEq<Cow<'a, OsStr>> for &'b OsStr
1.8.0 · source§impl<'a, 'b> PartialEq<Cow<'a, OsStr>> for OsStr
impl<'a, 'b> PartialEq<Cow<'a, OsStr>> for OsStr
1.8.0 · source§impl<'a> PartialEq<Cow<'a, OsStr>> for Path
impl<'a> PartialEq<Cow<'a, OsStr>> for Path
source§impl<'a, 'b> PartialEq<Cow<'a, OsStr>> for Utf8Path
impl<'a, 'b> PartialEq<Cow<'a, OsStr>> for Utf8Path
1.8.0 · source§impl<'a, 'b> PartialEq<Cow<'a, Path>> for &'b OsStr
impl<'a, 'b> PartialEq<Cow<'a, Path>> for &'b OsStr
1.6.0 · source§impl<'a, 'b> PartialEq<Cow<'a, Path>> for &'b Path
impl<'a, 'b> PartialEq<Cow<'a, Path>> for &'b Path
1.8.0 · source§impl<'a> PartialEq<Cow<'a, Path>> for OsStr
impl<'a> PartialEq<Cow<'a, Path>> for OsStr
1.6.0 · source§impl<'a> PartialEq<Cow<'a, Path>> for Path
impl<'a> PartialEq<Cow<'a, Path>> for Path
source§impl<'a, 'b> PartialEq<Cow<'a, Path>> for Utf8Path
impl<'a, 'b> PartialEq<Cow<'a, Path>> for Utf8Path
source§impl<'a, 'b> PartialEq<Cow<'a, Utf8Path>> for &'b Utf8Path
impl<'a, 'b> PartialEq<Cow<'a, Utf8Path>> for &'b Utf8Path
source§impl<'a, 'b> PartialEq<Cow<'a, Utf8Path>> for Utf8Path
impl<'a, 'b> PartialEq<Cow<'a, Utf8Path>> for Utf8Path
1.0.0 · source§impl<'a, 'b> PartialEq<Cow<'a, str>> for &'b str
impl<'a, 'b> PartialEq<Cow<'a, str>> for &'b str
source§impl<'a> PartialEq<Cow<'a, str>> for Rope
impl<'a> PartialEq<Cow<'a, str>> for Rope
1.0.0 · source§impl<'a, 'b> PartialEq<Cow<'a, str>> for String
impl<'a, 'b> PartialEq<Cow<'a, str>> for String
source§impl<'a, 'b> PartialEq<Cow<'a, str>> for Utf8Path
impl<'a, 'b> PartialEq<Cow<'a, str>> for Utf8Path
1.0.0 · source§impl<'a, 'b> PartialEq<Cow<'a, str>> for str
impl<'a, 'b> PartialEq<Cow<'a, str>> for str
1.0.0 · source§impl<'a, 'b, B, C> PartialEq<Cow<'b, C>> for Cow<'a, B>
impl<'a, 'b, B, C> PartialEq<Cow<'b, C>> for Cow<'a, B>
1.8.0 · source§impl<'a, 'b> PartialEq<Cow<'b, OsStr>> for &'a Path
impl<'a, 'b> PartialEq<Cow<'b, OsStr>> for &'a Path
source§impl<'a, 'b> PartialEq<Cow<'b, OsStr>> for &'a Utf8Path
impl<'a, 'b> PartialEq<Cow<'b, OsStr>> for &'a Utf8Path
source§impl<'a, 'b> PartialEq<Cow<'b, Path>> for &'a Utf8Path
impl<'a, 'b> PartialEq<Cow<'b, Path>> for &'a Utf8Path
source§impl<'a, 'b> PartialEq<Cow<'b, str>> for &'a Utf8Path
impl<'a, 'b> PartialEq<Cow<'b, str>> for &'a Utf8Path
1.8.0 · source§impl<'a, 'b> PartialEq<OsStr> for Cow<'a, OsStr>
impl<'a, 'b> PartialEq<OsStr> for Cow<'a, OsStr>
1.8.0 · source§impl<'a> PartialEq<OsStr> for Cow<'a, Path>
impl<'a> PartialEq<OsStr> for Cow<'a, Path>
1.8.0 · source§impl<'a, 'b> PartialEq<OsString> for Cow<'a, OsStr>
impl<'a, 'b> PartialEq<OsString> for Cow<'a, OsStr>
1.8.0 · source§impl<'a> PartialEq<OsString> for Cow<'a, Path>
impl<'a> PartialEq<OsString> for Cow<'a, Path>
1.8.0 · source§impl<'a> PartialEq<Path> for Cow<'a, OsStr>
impl<'a> PartialEq<Path> for Cow<'a, OsStr>
1.6.0 · source§impl<'a> PartialEq<Path> for Cow<'a, Path>
impl<'a> PartialEq<Path> for Cow<'a, Path>
1.8.0 · source§impl<'a> PartialEq<PathBuf> for Cow<'a, OsStr>
impl<'a> PartialEq<PathBuf> for Cow<'a, OsStr>
1.6.0 · source§impl<'a> PartialEq<PathBuf> for Cow<'a, Path>
impl<'a> PartialEq<PathBuf> for Cow<'a, Path>
source§impl<'a> PartialEq<Rope> for Cow<'a, str>
impl<'a> PartialEq<Rope> for Cow<'a, str>
source§impl<'a, 'b> PartialEq<RopeSlice<'a>> for Cow<'b, str>
impl<'a, 'b> PartialEq<RopeSlice<'a>> for Cow<'b, str>
source§impl<'a, 'b> PartialEq<Utf8Path> for Cow<'a, OsStr>
impl<'a, 'b> PartialEq<Utf8Path> for Cow<'a, OsStr>
source§impl<'a, 'b> PartialEq<Utf8Path> for Cow<'a, Path>
impl<'a, 'b> PartialEq<Utf8Path> for Cow<'a, Path>
source§impl<'a, 'b> PartialEq<Utf8Path> for Cow<'a, Utf8Path>
impl<'a, 'b> PartialEq<Utf8Path> for Cow<'a, Utf8Path>
source§impl<'a, 'b> PartialEq<Utf8Path> for Cow<'a, str>
impl<'a, 'b> PartialEq<Utf8Path> for Cow<'a, str>
source§impl<'a, 'b> PartialEq<Utf8PathBuf> for Cow<'a, OsStr>
impl<'a, 'b> PartialEq<Utf8PathBuf> for Cow<'a, OsStr>
source§fn eq(&self, other: &Utf8PathBuf) -> bool
fn eq(&self, other: &Utf8PathBuf) -> bool
self
and other
values to be equal, and is used
by ==
.source§impl<'a, 'b> PartialEq<Utf8PathBuf> for Cow<'a, Path>
impl<'a, 'b> PartialEq<Utf8PathBuf> for Cow<'a, Path>
source§fn eq(&self, other: &Utf8PathBuf) -> bool
fn eq(&self, other: &Utf8PathBuf) -> bool
self
and other
values to be equal, and is used
by ==
.source§impl<'a, 'b> PartialEq<Utf8PathBuf> for Cow<'a, Utf8Path>
impl<'a, 'b> PartialEq<Utf8PathBuf> for Cow<'a, Utf8Path>
source§fn eq(&self, other: &Utf8PathBuf) -> bool
fn eq(&self, other: &Utf8PathBuf) -> bool
self
and other
values to be equal, and is used
by ==
.source§impl<'a, 'b> PartialEq<Utf8PathBuf> for Cow<'a, str>
impl<'a, 'b> PartialEq<Utf8PathBuf> for Cow<'a, str>
source§fn eq(&self, other: &Utf8PathBuf) -> bool
fn eq(&self, other: &Utf8PathBuf) -> bool
self
and other
values to be equal, and is used
by ==
.1.0.0 · source§impl<T, U, A> PartialEq<Vec<U, A>> for Cow<'_, [T]>
impl<T, U, A> PartialEq<Vec<U, A>> for Cow<'_, [T]>
source§impl<T, U, A> PartialEq<Vec<U, A>> for Cow<'_, [T]>
impl<T, U, A> PartialEq<Vec<U, A>> for Cow<'_, [T]>
1.8.0 · source§impl<'a, 'b> PartialOrd<&'b OsStr> for Cow<'a, OsStr>
impl<'a, 'b> PartialOrd<&'b OsStr> for Cow<'a, OsStr>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read more1.8.0 · source§impl<'a, 'b> PartialOrd<&'b OsStr> for Cow<'a, Path>
impl<'a, 'b> PartialOrd<&'b OsStr> for Cow<'a, Path>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read more1.8.0 · source§impl<'a, 'b> PartialOrd<&'b Path> for Cow<'a, Path>
impl<'a, 'b> PartialOrd<&'b Path> for Cow<'a, Path>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read more1.8.0 · source§impl<'a, 'b> PartialOrd<&'a Path> for Cow<'b, OsStr>
impl<'a, 'b> PartialOrd<&'a Path> for Cow<'b, OsStr>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read moresource§impl<'a, 'b> PartialOrd<&'b Utf8Path> for Cow<'a, Utf8Path>
impl<'a, 'b> PartialOrd<&'b Utf8Path> for Cow<'a, Utf8Path>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read moresource§impl<'a, 'b> PartialOrd<&'a Utf8Path> for Cow<'b, OsStr>
impl<'a, 'b> PartialOrd<&'a Utf8Path> for Cow<'b, OsStr>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read moresource§impl<'a, 'b> PartialOrd<&'a Utf8Path> for Cow<'b, Path>
impl<'a, 'b> PartialOrd<&'a Utf8Path> for Cow<'b, Path>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read moresource§impl<'a, 'b> PartialOrd<&'a Utf8Path> for Cow<'b, str>
impl<'a, 'b> PartialOrd<&'a Utf8Path> for Cow<'b, str>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read more1.8.0 · source§impl<'a, 'b> PartialOrd<Cow<'a, OsStr>> for &'b OsStr
impl<'a, 'b> PartialOrd<Cow<'a, OsStr>> for &'b OsStr
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read more1.8.0 · source§impl<'a, 'b> PartialOrd<Cow<'a, OsStr>> for OsStr
impl<'a, 'b> PartialOrd<Cow<'a, OsStr>> for OsStr
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read more1.8.0 · source§impl<'a> PartialOrd<Cow<'a, OsStr>> for Path
impl<'a> PartialOrd<Cow<'a, OsStr>> for Path
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read moresource§impl<'a, 'b> PartialOrd<Cow<'a, OsStr>> for Utf8Path
impl<'a, 'b> PartialOrd<Cow<'a, OsStr>> for Utf8Path
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read more1.8.0 · source§impl<'a, 'b> PartialOrd<Cow<'a, Path>> for &'b OsStr
impl<'a, 'b> PartialOrd<Cow<'a, Path>> for &'b OsStr
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read more1.8.0 · source§impl<'a, 'b> PartialOrd<Cow<'a, Path>> for &'b Path
impl<'a, 'b> PartialOrd<Cow<'a, Path>> for &'b Path
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read more1.8.0 · source§impl<'a> PartialOrd<Cow<'a, Path>> for OsStr
impl<'a> PartialOrd<Cow<'a, Path>> for OsStr
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read more1.8.0 · source§impl<'a> PartialOrd<Cow<'a, Path>> for Path
impl<'a> PartialOrd<Cow<'a, Path>> for Path
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read moresource§impl<'a, 'b> PartialOrd<Cow<'a, Path>> for Utf8Path
impl<'a, 'b> PartialOrd<Cow<'a, Path>> for Utf8Path
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read moresource§impl<'a, 'b> PartialOrd<Cow<'a, Utf8Path>> for &'b Utf8Path
impl<'a, 'b> PartialOrd<Cow<'a, Utf8Path>> for &'b Utf8Path
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read moresource§impl<'a, 'b> PartialOrd<Cow<'a, Utf8Path>> for Utf8Path
impl<'a, 'b> PartialOrd<Cow<'a, Utf8Path>> for Utf8Path
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read moresource§impl<'a, 'b> PartialOrd<Cow<'a, str>> for Utf8Path
impl<'a, 'b> PartialOrd<Cow<'a, str>> for Utf8Path
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read more1.8.0 · source§impl<'a, 'b> PartialOrd<Cow<'b, OsStr>> for &'a Path
impl<'a, 'b> PartialOrd<Cow<'b, OsStr>> for &'a Path
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read moresource§impl<'a, 'b> PartialOrd<Cow<'b, OsStr>> for &'a Utf8Path
impl<'a, 'b> PartialOrd<Cow<'b, OsStr>> for &'a Utf8Path
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read moresource§impl<'a, 'b> PartialOrd<Cow<'b, Path>> for &'a Utf8Path
impl<'a, 'b> PartialOrd<Cow<'b, Path>> for &'a Utf8Path
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read moresource§impl<'a, 'b> PartialOrd<Cow<'b, str>> for &'a Utf8Path
impl<'a, 'b> PartialOrd<Cow<'b, str>> for &'a Utf8Path
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read more1.8.0 · source§impl<'a, 'b> PartialOrd<OsStr> for Cow<'a, OsStr>
impl<'a, 'b> PartialOrd<OsStr> for Cow<'a, OsStr>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read more1.8.0 · source§impl<'a> PartialOrd<OsStr> for Cow<'a, Path>
impl<'a> PartialOrd<OsStr> for Cow<'a, Path>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read more1.8.0 · source§impl<'a, 'b> PartialOrd<OsString> for Cow<'a, OsStr>
impl<'a, 'b> PartialOrd<OsString> for Cow<'a, OsStr>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read more1.8.0 · source§impl<'a> PartialOrd<OsString> for Cow<'a, Path>
impl<'a> PartialOrd<OsString> for Cow<'a, Path>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read more1.8.0 · source§impl<'a> PartialOrd<Path> for Cow<'a, OsStr>
impl<'a> PartialOrd<Path> for Cow<'a, OsStr>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read more1.8.0 · source§impl<'a> PartialOrd<Path> for Cow<'a, Path>
impl<'a> PartialOrd<Path> for Cow<'a, Path>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read more1.8.0 · source§impl<'a> PartialOrd<PathBuf> for Cow<'a, OsStr>
impl<'a> PartialOrd<PathBuf> for Cow<'a, OsStr>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read more1.8.0 · source§impl<'a> PartialOrd<PathBuf> for Cow<'a, Path>
impl<'a> PartialOrd<PathBuf> for Cow<'a, Path>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read moresource§impl<'a, 'b> PartialOrd<Utf8Path> for Cow<'a, OsStr>
impl<'a, 'b> PartialOrd<Utf8Path> for Cow<'a, OsStr>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read moresource§impl<'a, 'b> PartialOrd<Utf8Path> for Cow<'a, Path>
impl<'a, 'b> PartialOrd<Utf8Path> for Cow<'a, Path>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read moresource§impl<'a, 'b> PartialOrd<Utf8Path> for Cow<'a, Utf8Path>
impl<'a, 'b> PartialOrd<Utf8Path> for Cow<'a, Utf8Path>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read moresource§impl<'a, 'b> PartialOrd<Utf8Path> for Cow<'a, str>
impl<'a, 'b> PartialOrd<Utf8Path> for Cow<'a, str>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read moresource§impl<'a, 'b> PartialOrd<Utf8PathBuf> for Cow<'a, OsStr>
impl<'a, 'b> PartialOrd<Utf8PathBuf> for Cow<'a, OsStr>
source§fn partial_cmp(&self, other: &Utf8PathBuf) -> Option<Ordering>
fn partial_cmp(&self, other: &Utf8PathBuf) -> Option<Ordering>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read moresource§impl<'a, 'b> PartialOrd<Utf8PathBuf> for Cow<'a, Path>
impl<'a, 'b> PartialOrd<Utf8PathBuf> for Cow<'a, Path>
source§fn partial_cmp(&self, other: &Utf8PathBuf) -> Option<Ordering>
fn partial_cmp(&self, other: &Utf8PathBuf) -> Option<Ordering>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read moresource§impl<'a, 'b> PartialOrd<Utf8PathBuf> for Cow<'a, Utf8Path>
impl<'a, 'b> PartialOrd<Utf8PathBuf> for Cow<'a, Utf8Path>
source§fn partial_cmp(&self, other: &Utf8PathBuf) -> Option<Ordering>
fn partial_cmp(&self, other: &Utf8PathBuf) -> Option<Ordering>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read moresource§impl<'a, 'b> PartialOrd<Utf8PathBuf> for Cow<'a, str>
impl<'a, 'b> PartialOrd<Utf8PathBuf> for Cow<'a, str>
source§fn partial_cmp(&self, other: &Utf8PathBuf) -> Option<Ordering>
fn partial_cmp(&self, other: &Utf8PathBuf) -> Option<Ordering>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read more1.0.0 · source§impl<'a, B> PartialOrd for Cow<'a, B>
impl<'a, B> PartialOrd for Cow<'a, B>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read moresource§impl<'a, T> Serialize for Cow<'a, T>
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&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,
source§impl<'a, T> ToTokens for Cow<'a, T>
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source§fn to_tokens(&self, tokens: &mut TokenStream)
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source§fn to_token_stream(&self) -> TokenStream
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source§fn into_token_stream(self) -> TokenStreamwhere
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§type Err = <String as FromRouteSegment>::Err
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