pub trait AsMut<T> where T: ?Sized, { fn as_mut(&mut self) -> &mut TⓘNotable traits for &'_ mut Fimpl<'_, F> Future for &'_ mut F where F: Unpin + Future + ?Sized, type Output = <F as Future>::Output;impl<'_, I> Iterator for &'_ mut I where I: Iterator + ?Sized, type Item = <I as Iterator>::Item;impl<R: Read + ?Sized, '_> Read for &'_ mut Rimpl<W: Write + ?Sized, '_> Write for &'_ mut W; }
Used to do a cheap mutable-to-mutable reference conversion.
This trait is similar to AsRef
but used for converting between mutable references. If you need to do a costly conversion it is better to implement From
with type &mut T
or write a custom function.
Note: This trait must not fail. If the conversion can fail, use a dedicated method which returns an Option<T>
or a Result<T, E>
.
AsMut
auto-dereferences if the inner type is a mutable reference (e.g.: foo.as_mut()
will work the same if foo
has type &mut Foo
or &mut &mut Foo
)Using AsMut
as trait bound for a generic function we can accept all mutable references that can be converted to type &mut T
. Because Box<T>
implements AsMut<T>
we can write a function add_one
that takes all arguments that can be converted to &mut u64
. Because Box<T>
implements AsMut<T>
, add_one
accepts arguments of type &mut Box<u64>
as well:
fn add_one<T: AsMut<u64>>(num: &mut T) { *num.as_mut() += 1; } let mut boxed_num = Box::new(0); add_one(&mut boxed_num); assert_eq!(*boxed_num, 1);
fn as_mut(&mut self) -> &mut TⓘNotable traits for &'_ mut F
impl<'_, F> Future for &'_ mut F where
F: Unpin + Future + ?Sized,
type Output = <F as Future>::Output;
impl<'_, I> Iterator for &'_ mut I where
I: Iterator + ?Sized,
type Item = <I as Iterator>::Item;
impl<R: Read + ?Sized, '_> Read for &'_ mut R
impl<W: Write + ?Sized, '_> Write for &'_ mut W
Performs the conversion.
impl AsMut<str> for String
[src]
impl<'_, T, U> AsMut<U> for &'_ mut T where
T: AsMut<U> + ?Sized,
U: ?Sized,
[src]
fn as_mut(&mut self) -> &mut UⓘNotable traits for &'_ mut F
impl<'_, F> Future for &'_ mut F where
F: Unpin + Future + ?Sized,
type Output = <F as Future>::Output;
impl<'_, I> Iterator for &'_ mut I where
I: Iterator + ?Sized,
type Item = <I as Iterator>::Item;
impl<R: Read + ?Sized, '_> Read for &'_ mut R
impl<W: Write + ?Sized, '_> Write for &'_ mut W
[src]
impl<T> AsMut<[T]> for [T]
[src]
fn as_mut(&mut self) -> &mut [T]ⓘNotable traits for &'_ [u8]
impl<'_> Read for &'_ [u8]
impl<'_> Write for &'_ mut [u8]
[src]
impl<T> AsMut<[T]> for Vec<T>
[src]
fn as_mut(&mut self) -> &mut [T]ⓘNotable traits for &'_ [u8]
impl<'_> Read for &'_ [u8]
impl<'_> Write for &'_ mut [u8]
[src]
impl<T> AsMut<Vec<T>> for Vec<T>
[src]
impl<T> AsMut<T> for Box<T> where
T: ?Sized,
[src]
fn as_mut(&mut self) -> &mut TⓘNotable traits for &'_ mut F
impl<'_, F> Future for &'_ mut F where
F: Unpin + Future + ?Sized,
type Output = <F as Future>::Output;
impl<'_, I> Iterator for &'_ mut I where
I: Iterator + ?Sized,
type Item = <I as Iterator>::Item;
impl<R: Read + ?Sized, '_> Read for &'_ mut R
impl<W: Write + ?Sized, '_> Write for &'_ mut W
[src]
impl<T, const N: usize> AsMut<[T]> for [T; N]
[src]
© 2010 The Rust Project Developers
Licensed under the Apache License, Version 2.0 or the MIT license, at your option.
https://doc.rust-lang.org/std/convert/trait.AsMut.html