Struct MutBorrow

pub struct MutBorrow<T> { /* private fields */ }

Wrapper type that allows creating a self-referential type that hold a mutable borrow &mut T.

Example usage:

use self_cell::{self_cell, MutBorrow};

type MutStringRef<'a> = &'a mut String;

self_cell!(
    struct MutStringCell {
        owner: MutBorrow<String>,

        #[covariant]
        dependent: MutStringRef,
    }
);

let mut cell = MutStringCell::new(MutBorrow::new("abc".into()), |owner| owner.borrow_mut());
cell.with_dependent_mut(|_owner, dependent| {
    assert_eq!(dependent, &"abc");
    dependent.pop();
    assert_eq!(dependent, &"ab");
});

let recovered_owner: String = cell.into_owner().into_inner();
assert_eq!(recovered_owner, "ab");

Implementations

impl<T> MutBorrow<T>

pub fn new(value: T) -> Self

Constructs a new MutBorrow.

pub fn borrow_mut(&self) -> &mut T

Obtains a mutable reference to the underlying data.

This function can only sensibly be used in the builder function. Afterwards, it’s impossible to access the inner value, with the exception of MutBorrow::into_inner.

Panics

Will panic if called anywhere but in the dependent constructor. Will also panic if called more than once.

pub fn into_inner(self) -> T

Consumes self and returns the wrapped value.

Trait Implementations

impl<T: Send> Sync for MutBorrow<T>