Struct gc::GcCell

pub struct GcCell<T: ?Sized + 'static> { /* private fields */ }

A mutable memory location with dynamically checked borrow rules that can be used inside of a garbage-collected pointer.

This object is a RefCell that can be used inside of a Gc<T>.

Implementations

impl<T> GcCell<T>

pub fn new(value: T) -> Self

Creates a new GcCell containing value.

pub fn into_inner(self) -> T

Consumes the GcCell, returning the wrapped value.

impl<T: ?Sized> GcCell<T>

pub fn borrow(&self) -> GcCellRef<'_, T>

Immutably borrows the wrapped value.

The borrow lasts until the returned GcCellRef exits scope. Multiple immutable borrows can be taken out at the same time.

Panics

Panics if the value is currently mutably borrowed.

impl<T: Trace + ?Sized> GcCell<T>

pub fn borrow_mut(&self) -> GcCellRefMut<'_, T>

Mutably borrows the wrapped value.

The borrow lasts until the returned GcCellRefMut exits scope. The value cannot be borrowed while this borrow is active.

Panics

Panics if the value is currently borrowed.

impl<T: ?Sized> GcCell<T>

pub fn try_borrow(&self) -> Result<GcCellRef<'_, T>, BorrowError>

Immutably borrows the wrapped value, returning an error if the value is currently mutably borrowed.

The borrow lasts until the returned GcCellRef exits scope. Multiple immutable borrows can be taken out at the same time.

This is the non-panicking variant of borrow.

Examples

use gc::GcCell;

let c = GcCell::new(5);

{
    let m = c.borrow_mut();
    assert!(c.try_borrow().is_err());
}

{
    let m = c.borrow();
    assert!(c.try_borrow().is_ok());
}

impl<T: Trace + ?Sized> GcCell<T>

pub fn try_borrow_mut(&self) -> Result<GcCellRefMut<'_, T>, BorrowMutError>

Mutably borrows the wrapped value, returning an error if the value is currently borrowed.

The borrow lasts until the returned GcCellRefMut exits scope. The value cannot be borrowed while this borrow is active.

This is the non-panicking variant of borrow_mut.

Examples

use gc::GcCell;

let c = GcCell::new(5);

{
    let m = c.borrow();
    assert!(c.try_borrow_mut().is_err());
}

assert!(c.try_borrow_mut().is_ok());

Trait Implementations

impl<T: Clone> Clone for GcCell<T>

fn clone(&self) -> Self

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<T: ?Sized + Debug> Debug for GcCell<T>

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

Formats the value using the given formatter.

impl<T: Default> Default for GcCell<T>

fn default() -> Self

Returns the “default value” for a type.

impl<T: ?Sized> Finalize for GcCell<T>

fn finalize(&self)

impl<T: ?Sized + Ord> Ord for GcCell<T>

fn cmp(&self, other: &GcCell<T>) -> Ordering

This method returns an Ordering between self and other.

impl<T: ?Sized + PartialEq> PartialEq<GcCell<T>> for GcCell<T>

fn eq(&self, other: &Self) -> bool

This method tests for self and other values to be equal, and is used by ==.

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

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

impl<T: ?Sized + PartialOrd> PartialOrd<GcCell<T>> for GcCell<T>

fn partial_cmp(&self, other: &Self) -> Option<Ordering>

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

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

This method tests less than (for self and other) and is used by the < operator.

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

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

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

This method tests greater than (for self and other) and is used by the > operator.

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

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

impl<T: Trace + ?Sized> Trace for GcCell<T>

unsafe fn trace(&self)

Marks all contained Gcs.

unsafe fn root(&self)

Increments the root-count of all contained Gcs.

unsafe fn unroot(&self)

Decrements the root-count of all contained Gcs.

fn finalize_glue(&self)

Runs Finalize::finalize() on this object and all contained subobjects

impl<T: ?Sized + Eq> Eq for GcCell<T>

impl<T: ?Sized + Send> Send for GcCell<T>