std::convert::AsMut - Rust
Description: API documentation for the Rust `AsMut` trait in crate `std`.
Keywords: rust, rustlang, rust-lang, AsMut

# Trait std::convert::AsMut 1.0.0 [−] [src]

    pub trait AsMut<T> where T: ?Sized {
        fn as_mut(&mut self) -> &mut T;
    }

A cheap, mutable reference-to-mutable reference conversion.

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>`.

# Examples

`Box<T>` implements `AsMut<T>`:

    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);Run

# Generic Impls

- `AsMut` auto-dereferences if the inner type is a reference or a mutable reference (e.g.: `foo.as_ref()` will work the same if `foo` has type `&mut Foo` or `&&mut Foo`)

## Required Methods

### `fn as_mut(&mut self) -> &mut T`

Performs the conversion.

## Implementors

- `impl<T> AsMut<T> for Box<T> where T: ?Sized`
- `impl<T> AsMut<Vec<T>> for Vec<T>`
- `impl<T> AsMut<[T]> for Vec<T>`
- `impl<'a, T, U> AsMut<U> for &'a mut T where T: AsMut<U> + ?Sized, U: ?Sized`
- `impl<T> AsMut<[T]> for [T]`
- `impl<T> AsMut<[T]> for [T; 0]`
- `impl<T> AsMut<[T]> for [T; 1]`
- `impl<T> AsMut<[T]> for [T; 2]`
- `impl<T> AsMut<[T]> for [T; 3]`
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- `impl<T> AsMut<[T]> for [T; 5]`
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- `impl<T> AsMut<[T]> for [T; 9]`
- `impl<T> AsMut<[T]> for [T; 10]`
- `impl<T> AsMut<[T]> for [T; 11]`
- `impl<T> AsMut<[T]> for [T; 12]`
- `impl<T> AsMut<[T]> for [T; 13]`
- `impl<T> AsMut<[T]> for [T; 14]`
- `impl<T> AsMut<[T]> for [T; 15]`
- `impl<T> AsMut<[T]> for [T; 16]`
- `impl<T> AsMut<[T]> for [T; 17]`
- `impl<T> AsMut<[T]> for [T; 18]`
- `impl<T> AsMut<[T]> for [T; 19]`
- `impl<T> AsMut<[T]> for [T; 20]`
- `impl<T> AsMut<[T]> for [T; 21]`
- `impl<T> AsMut<[T]> for [T; 22]`
- `impl<T> AsMut<[T]> for [T; 23]`
- `impl<T> AsMut<[T]> for [T; 24]`
- `impl<T> AsMut<[T]> for [T; 25]`
- `impl<T> AsMut<[T]> for [T; 26]`
- `impl<T> AsMut<[T]> for [T; 27]`
- `impl<T> AsMut<[T]> for [T; 28]`
- `impl<T> AsMut<[T]> for [T; 29]`
- `impl<T> AsMut<[T]> for [T; 30]`
- `impl<T> AsMut<[T]> for [T; 31]`
- `impl<T> AsMut<[T]> for [T; 32]`

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