pub trait BorrowMut<Borrowed: ?Sized>: Borrow<Borrowed> { fn borrow_mut(&mut self) -> &mut Borrowed; }
A trait for mutably borrowing data.
As a companion to Borrow<T> this trait allows a type to borrow as an underlying type by providing a mutable reference. See Borrow<T> for more information on borrowing as another type.
Borrow<T>
Mutably borrows from an owned value.
use std::borrow::BorrowMut; fn check<T: BorrowMut<[i32]>>(mut v: T) { assert_eq!(&mut [1, 2, 3], v.borrow_mut()); } let v = vec![1, 2, 3]; check(v);