Struct gc_arena::GcCell

pub struct GcCell<'gc, T: 'gc + Collect>(_);

A garbage collected pointer to a type T that may be safely mutated. When a type that may hold Gc pointers is mutated, it may adopt new Gc pointers, and in order for this to be safe this must be accompanied by a call to Gc::write_barrier. This type wraps the given T in a RefCell in such a way that writing to the RefCell is always accompanied by a call to Gc::write_barrier.

Methods

impl<'gc, T: 'gc + Collect> GcCell<'gc, T>

pub fn allocate(mc: MutationContext<'gc, '_>, t: T) -> GcCell<'gc, T>

pub fn ptr_eq(this: GcCell<'gc, T>, other: GcCell<'gc, T>) -> bool

pub fn as_ptr(self) -> *mut T

pub fn read<'a>(&'a self) -> Ref<'a, T>

pub fn try_read<'a>(&'a self) -> Result<Ref<'a, T>, BorrowError>

pub fn write<'a>(&'a self, mc: MutationContext<'gc, '_>) -> RefMut<'a, T>

pub fn try_write<'a>(
    &'a self,
    mc: MutationContext<'gc, '_>
) -> Result<RefMut<'a, T>, BorrowMutError>

Trait Implementations

impl<'gc, T: 'gc + Collect> Collect for GcCell<'gc, T>

fn trace(&self, cc: CollectionContext)

Must call Collect::trace on all held Gc pointers. If this type holds inner types that implement Collect, a valid implementation would simply call Collect::trace on all the held values to ensure this.

fn needs_trace() -> bool where
    Self: Sized, 

As an optimization, if this type can never hold a Gc pointer and trace is unnecessary to call, you may implement this method and return false. The default implementation returns true, signaling that Collect::trace must be called.

impl<'gc, T: Collect + 'gc> Copy for GcCell<'gc, T>

impl<'gc, T: Collect + 'gc> Clone for GcCell<'gc, T>

fn clone(&self) -> GcCell<'gc, T>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<'gc, T: 'gc + Collect + Debug> Debug for GcCell<'gc, T>

fn fmt(&self, fmt: &mut Formatter) -> Result

Formats the value using the given formatter.