# Trait bitflags::__core::ops::DerefMut [−] [src]

    pub trait DerefMut: Deref {
        fn deref_mut(&mut self) -> &mut Self::Target;
    }

The `DerefMut` trait is used to specify the functionality of dereferencing mutably like `*v = 1;`

`DerefMut` also enables '`Deref` coercions'.

# Examples

A struct with a single field which is modifiable via dereferencing the struct.

    use std::ops::{Deref, DerefMut};

    struct DerefMutExample<T> {
        value: T
    }

    impl<T> Deref for DerefMutExample<T> {
        type Target = T;

        fn deref<'a>(&'a self) -> &'a T {
            &self.value
        }
    }

    impl<T> DerefMut for DerefMutExample<T> {
        fn deref_mut<'a>(&'a mut self) -> &'a mut T {
            &mut self.value
        }
    }

    fn main() {
        let mut x = DerefMutExample { value: 'a' };
        *x = 'b';
        assert_eq!('b', *x);
    }

## Required Methods

### `fn deref_mut(&mut self) -> &mut Self::Target`

The method called to mutably dereference a value

## Implementors

- `impl<T> DerefMut for AssertUnwindSafe<T>`
- `impl<T> DerefMut for AssertRecoverSafe<T>`
- `impl<'mutex, T> DerefMut for MutexGuard<'mutex, T> where T: ?Sized`
- `impl<'rwlock, T> DerefMut for RwLockWriteGuard<'rwlock, T> where T: ?Sized`
- `impl<T> DerefMut for Vec<T>`
- `impl<T> DerefMut for Box<T> where T: ?Sized`
- `impl<'a, T> DerefMut for &'a mut T where T: ?Sized`
- `impl<'b, T> DerefMut for RefMut<'b, T> where T: ?Sized`
- `impl DerefMut for String`

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