Struct OwningRefMut 

pub struct OwningRefMut<'t, O, T>
where
    T: ?Sized,
{ /* private fields */ }

An mutable owning reference.

This wraps an owner O and a reference &mut T pointing at something reachable from O::Target while keeping the ability to move self around.

The owner is usually a pointer that points at some base type.

For more details and examples, see the module and method docs.

Implementations

impl<'t, O, T> OwningRefMut<'t, O, T>

where T: ?Sized,

pub fn new(o: O) -> OwningRefMut<'t, O, T>

where O: StableDeref<Target = T> + DerefMut,

Creates a new owning reference from a owner initialized to the direct dereference of it.

Example

extern crate owning_ref;
use owning_ref::OwningRefMut;

fn main() {
    let owning_ref_mut = OwningRefMut::new(Box::new(42));
    assert_eq!(*owning_ref_mut, 42);
}

pub unsafe fn new_assert_stable_address(o: O) -> OwningRefMut<'t, O, T>

where O: DerefMut<Target = T>,

Like new, but doesn’t require O to implement the StableAddress trait. Instead, the caller is responsible to make the same promises as implementing the trait.

This is useful for cases where coherence rules prevents implementing the trait without adding a dependency to this crate in a third-party library.

pub unsafe fn map<F, U>(self, f: F) -> OwningRef<'t, O, U>

where O: StableDeref, F: FnOnce(&mut T) -> &U, U: ?Sized,

👎Deprecated since 0.5.0:

unsafe function. can create aliased references

Converts self into a new shared owning reference that points at something reachable from the previous one.

This can be a reference to a field of U, something reachable from a field of U, or even something unrelated with a 'static lifetime.

Example

extern crate owning_ref;
use owning_ref::OwningRefMut;

fn main() {
    let owning_ref_mut = OwningRefMut::new(Box::new([1, 2, 3, 4]));

    // create a owning reference that points at the
    // third element of the array.
    let owning_ref = unsafe { owning_ref_mut.map(|array| &array[2]) };
    assert_eq!(*owning_ref, 3);
}

pub fn map_mut<F, U>(self, f: F) -> OwningRefMut<'t, O, U>

where O: StableDeref, F: FnOnce(&mut T) -> &mut U, U: ?Sized,

Converts self into a new mutable owning reference that points at something reachable from the previous one.

This can be a reference to a field of U, something reachable from a field of U, or even something unrelated with a 'static lifetime.

Example

extern crate owning_ref;
use owning_ref::OwningRefMut;

fn main() {
    let owning_ref_mut = OwningRefMut::new(Box::new([1, 2, 3, 4]));

    // create a owning reference that points at the
    // third element of the array.
    let owning_ref_mut = owning_ref_mut.map_mut(|array| &mut array[2]);
    assert_eq!(*owning_ref_mut, 3);
}

pub unsafe fn try_map<F, U, E>(self, f: F) -> Result<OwningRef<'t, O, U>, E>

where O: StableDeref, F: FnOnce(&mut T) -> Result<&U, E>, U: ?Sized,

👎Deprecated since 0.5.0:

unsafe function. can create aliased references

Tries to convert self into a new shared owning reference that points at something reachable from the previous one.

This can be a reference to a field of U, something reachable from a field of U, or even something unrelated with a 'static lifetime.

Example

extern crate owning_ref;
use owning_ref::OwningRefMut;

fn main() {
    let owning_ref_mut = OwningRefMut::new(Box::new([1, 2, 3, 4]));

    // create a owning reference that points at the
    // third element of the array.
    let owning_ref = unsafe {
        owning_ref_mut.try_map(|array| {
            if array[2] == 3 { Ok(&array[2]) } else { Err(()) }
        })
    };
    assert_eq!(*owning_ref.unwrap(), 3);
}

pub fn try_map_mut<F, U, E>(self, f: F) -> Result<OwningRefMut<'t, O, U>, E>

where O: StableDeref, F: FnOnce(&mut T) -> Result<&mut U, E>, U: ?Sized,

Tries to convert self into a new mutable owning reference that points at something reachable from the previous one.

This can be a reference to a field of U, something reachable from a field of U, or even something unrelated with a 'static lifetime.

Example

extern crate owning_ref;
use owning_ref::OwningRefMut;

fn main() {
    let owning_ref_mut = OwningRefMut::new(Box::new([1, 2, 3, 4]));

    // create a owning reference that points at the
    // third element of the array.
    let owning_ref_mut = owning_ref_mut.try_map_mut(|array| {
        if array[2] == 3 { Ok(&mut array[2]) } else { Err(()) }
    });
    assert_eq!(*owning_ref_mut.unwrap(), 3);
}

pub unsafe fn map_owner<F, P>(self, f: F) -> OwningRefMut<'t, P, T>

where O: StableDeref, P: StableDeref, F: FnOnce(O) -> P,

Converts self into a new owning reference with a different owner type.

The new owner type needs to still contain the original owner in some way so that the reference into it remains valid. This function is marked unsafe because the user needs to manually uphold this guarantee.

pub fn map_owner_box(self) -> OwningRefMut<'t, Box<O>, T>

Converts self into a new owning reference where the owner is wrapped in an additional Box<O>.

This can be used to safely erase the owner of any OwningRefMut<'_, O, T> to a OwningRefMut<'_, Box<dyn Erased>, T>.

pub fn erase_owner<'a>( self, ) -> OwningRefMut<'t, <O as IntoErased<'a>>::Erased, T>

where O: IntoErased<'a>,

Erases the concrete base type of the owner with a trait object.

This allows mixing of owned references with different owner base types.

Example

extern crate owning_ref;
use owning_ref::{OwningRefMut, Erased};

fn main() {
    // NB: Using the concrete types here for explicitnes.
    // For less verbose code type aliases like `BoxRef` are provided.

    let owning_ref_mut_a: OwningRefMut<'_, Box<[i32; 4]>, [i32; 4]>
        = OwningRefMut::new(Box::new([1, 2, 3, 4]));

    let owning_ref_mut_b: OwningRefMut<'_, Box<Vec<(i32, bool)>>, Vec<(i32, bool)>>
        = OwningRefMut::new(Box::new(vec![(0, false), (1, true)]));

    let owning_ref_mut_a: OwningRefMut<'_, Box<[i32; 4]>, i32>
        = owning_ref_mut_a.map_mut(|a| &mut a[0]);

    let owning_ref_mut_b: OwningRefMut<'_, Box<Vec<(i32, bool)>>, i32>
        = owning_ref_mut_b.map_mut(|a| &mut a[1].0);

    let owning_refs_mut: [OwningRefMut<'_, Box<dyn Erased>, i32>; 2]
        = [owning_ref_mut_a.erase_owner(), owning_ref_mut_b.erase_owner()];

    assert_eq!(*owning_refs_mut[0], 1);
    assert_eq!(*owning_refs_mut[1], 1);
}

pub unsafe fn as_owner(&self) -> &O

👎Deprecated since 0.5.0:

unsafe function. can create aliased references

A reference to the underlying owner.

pub unsafe fn as_owner_mut(&mut self) -> &mut O

👎Deprecated since 0.5.0:

unsafe function. can create aliased references

A mutable reference to the underlying owner.

pub fn into_owner(self) -> O

Discards the reference and retrieves the owner.

Trait Implementations

impl<'t, O, T> AsMut<T> for OwningRefMut<'t, O, T>

where T: ?Sized,

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

Converts this type into a mutable reference of the (usually inferred) input type.

impl<'t, O, T> AsRef<T> for OwningRefMut<'t, O, T>

where T: ?Sized,

fn as_ref(&self) -> &T

Converts this type into a shared reference of the (usually inferred) input type.

impl<'t, O, T> Borrow<T> for OwningRefMut<'t, O, T>

where T: ?Sized,

fn borrow(&self) -> &T

Immutably borrows from an owned value.

impl<'t, O, T> BorrowMut<T> for OwningRefMut<'t, O, T>

where T: ?Sized,

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

Mutably borrows from an owned value.

impl<'t, O, T> Debug for OwningRefMut<'t, O, T>

where O: Debug, T: Debug + ?Sized,

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl<'t, O, T> Deref for OwningRefMut<'t, O, T>

where T: ?Sized,

type Target = T

The resulting type after dereferencing.

fn deref(&self) -> &T

Dereferences the value.

impl<'t, O, T> DerefMut for OwningRefMut<'t, O, T>

where T: ?Sized,

fn deref_mut(&mut self) -> &mut T

Mutably dereferences the value.

impl<'t, O, T> Eq for OwningRefMut<'t, O, T>

where T: Eq + ?Sized,

impl<'t, O, T> From<O> for OwningRefMut<'t, O, T>

where O: StableDeref<Target = T> + DerefMut, T: ?Sized,

fn from(owner: O) -> OwningRefMut<'t, O, T>

Converts to this type from the input type.

impl<'t, O, T> Hash for OwningRefMut<'t, O, T>

where T: Hash + ?Sized,

fn hash<H>(&self, state: &mut H)

where H: Hasher,

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl<'t, O, T> Ord for OwningRefMut<'t, O, T>

where T: Ord + ?Sized,

fn cmp(&self, other: &OwningRefMut<'t, O, T>) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl<'t, O, T> PartialEq for OwningRefMut<'t, O, T>

where T: PartialEq + ?Sized,

fn eq(&self, other: &OwningRefMut<'t, O, T>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'t, O, T> PartialOrd for OwningRefMut<'t, O, T>

where T: PartialOrd + ?Sized,

fn partial_cmp(&self, other: &OwningRefMut<'t, O, T>) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<'t, O, T> Send for OwningRefMut<'t, O, T>

where O: Send, &'a mut T: for<'a> Send, T: ?Sized,

impl<'t, O, T> StableDeref for OwningRefMut<'t, O, T>

where T: ?Sized,

impl<'t, O, T> Sync for OwningRefMut<'t, O, T>

where O: Sync, &'a mut T: for<'a> Sync, T: ?Sized,