Struct ManagedArena 

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

Shared language-neutral arena, node, edge, and retention building blocks. Bounded storage for managed objects, independent of language and collector policy.

Implementations

impl<T> ManagedArena<T>

pub fn new(policy: HardCappedRetainPolicy) -> ManagedArena<T>

Creates an empty arena using the hard-capped retain policy.

pub const fn trace_contract_version(&self) -> TraceContractVersion

Returns the tracing contract version.

pub fn len(&self) -> usize

Returns the number of live objects.

pub fn is_empty(&self) -> bool

Reports whether the arena contains no objects.

pub const fn mutation_epoch(&self) -> u64

Returns the epoch advanced by every graph-affecting arena mutation.

pub fn allocate(&mut self, object: T) -> Result<ManagedHandle, ArenaError>

Allocates atomically after checking the cap and identity space.

pub fn get(&self, handle: ManagedHandle) -> Result<&T, ArenaError>

Returns a shared object reference, refusing stale handles.

pub fn get_mut(&mut self, handle: ManagedHandle) -> Result<&mut T, ArenaError>

Returns a mutable object reference, refusing stale handles.

pub fn upgrade(&mut self, weak: WeakHandle) -> Result<ManagedHandle, ArenaError>

Upgrades a weak handle only while its object remains live.

pub fn handle(&self, id: ManagedId) -> Result<ManagedHandle, ArenaError>

Resolves a tracing identity to a live handle for collector operations.

pub fn root( &mut self, handle: ManagedHandle, ) -> Result<RootedHandle, ArenaError>

Registers a root after validating the handle.

pub fn release_root( &mut self, rooted: RootedHandle, ) -> Result<ManagedHandle, ArenaError>

Releases exactly one matching root registration.

pub fn remove(&mut self, handle: ManagedHandle) -> Result<T, ArenaError>

Removes an unrooted object, making all handles to it stale.

pub fn clear_weak_edge( &mut self, owner: ManagedHandle, edge: EdgeId, expected: WeakHandle, ) -> Result<bool, ArenaError>

where T: ManagedObject,

Clears a weak edge through the owning object’s at-most-once operation.

pub fn sweep_at_epoch( &mut self, expected_epoch: u64, objects: &[ManagedId], ) -> Result<Vec<ManagedId>, ArenaError>

Atomically removes an allocation-ordered set selected from expected_epoch.

Every identity and root condition is checked before the first slot changes.

pub fn apply_collection_at_epoch( &mut self, expected_epoch: u64, weak: &[(ManagedId, EdgeId, ManagedId)], ephemerons: &[(ManagedId, EdgeId, ManagedId, ManagedId)], swept: &[ManagedId], ) -> Result<CollectionMutationReceipt, ArenaError>

where T: ManagedObject,

Applies a collector plan atomically at expected_epoch.

Kept-alive objects from that epoch are retained. Weak and ephemeron entries are cleared before unreachable objects are removed, and every conditional clear is intrinsically at most once.

pub fn safepoint<R>( &mut self, trace: impl FnOnce(&TraceSnapshot<'_, T>) -> R, ) -> Result<(R, SafepointReceipt), ArenaError>

where T: ManagedObject,

Runs a read-only tracing callback at a deterministic safepoint.

pub fn teardown(&mut self) -> TeardownReceipt

Tears down all storage and roots, returning allocation-ordered evidence.

impl<T> ManagedArena<T>

where T: RoleBearingManagedObject,

pub fn replace_role( &mut self, handle: ManagedHandle, role: <T as RoleBearingManagedObject>::Role, ) -> Result<<T as RoleBearingManagedObject>::Role, ArenaError>

Replaces caller-owned role evidence without advancing the graph epoch.

pub fn project_roles( &mut self, limit: usize, ) -> Result<RoleProjectionReceipt<<T as RoleBearingManagedObject>::Role>, RoleProjectionError>

where <T as RoleBearingManagedObject>::Role: Clone,

Projects optional owner-role evidence at a read-only safepoint.

Admission is checked before invoking role, and rows follow managed id order. The projection observes objects but is not visible to tracing or collector policy.