Trait GetManyMutExt

pub unsafe trait GetManyMutExt {
    type Element;

    // Required methods
    fn get_many_mut<const N: usize>(
        &mut self,
        indices: [usize; N],
    ) -> Result<[&mut Self::Element; N], GetManyMutError<N>>;
    unsafe fn get_many_unchecked_mut<const N: usize>(
        &mut self,
        indices: [usize; N],
    ) -> [&mut Self::Element; N];
}

Extension trait for get_many_mut.

Required Associated Types

type Element

Required Methods

fn get_many_mut<const N: usize>( &mut self, indices: [usize; N], ) -> Result<[&mut Self::Element; N], GetManyMutError<N>>

Returns mutable references to many indices at once.

Returns an error if any index is out-of-bounds, or if the same index was passed more than once.

Examples

use get_many_mut::GetManyMutExt;

let v = &mut [1, 2, 3];
if let Ok([a, b]) = v.get_many_mut([0, 2]) {
    *a = 413;
    *b = 612;
}
assert_eq!(v, &[413, 2, 612]);

use get_many_mut::GetManyMutExt;

let v = &mut [1, 2, 3];
v.get_many_mut([0, 2, 0]).unwrap();

unsafe fn get_many_unchecked_mut<const N: usize>( &mut self, indices: [usize; N], ) -> [&mut Self::Element; N]

Returns mutable references to many indices at once, without doing any checks.

For a safe alternative see get_many_mut.

Safety

Calling this method with overlapping or out-of-bounds indices is undefined behavior even if the resulting references are not used.

Examples

use get_many_mut::GetManyMutExt;

let x = &mut [1, 2, 4];

unsafe {
    let [a, b] = x.get_many_unchecked_mut([0, 2]);
    *a *= 10;
    *b *= 100;
}
assert_eq!(x, &[10, 2, 400]);

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementations on Foreign Types

impl<T> GetManyMutExt for [T]

type Element = T

fn get_many_mut<const N: usize>( &mut self, indices: [usize; N], ) -> Result<[&mut Self::Element; N], GetManyMutError<N>>

unsafe fn get_many_unchecked_mut<const N: usize>( &mut self, indices: [usize; N], ) -> [&mut T; N]

impl<T, const M: usize> GetManyMutExt for [T; M]

type Element = T

fn get_many_mut<const N: usize>( &mut self, indices: [usize; N], ) -> Result<[&mut Self::Element; N], GetManyMutError<N>>

unsafe fn get_many_unchecked_mut<const N: usize>( &mut self, indices: [usize; N], ) -> [&mut T; N]

Implementors