Struct EntityList 

pub struct EntityList<I: IEntityListNodeID> {
    pub head: I,
    pub tail: I,
    pub len: Cell<usize>,
}

Doubly-linked list view over entities stored in an EntityAlloc.

Logical structure: the list uses head/tail sentinel nodes (allocated via the entity allocator) and maintains EntityListNodeHead inside each entity to chain nodes. Physical structure: no extra heap nodes are allocated—linkage is stored inline within entity storage.

The list invokes signals (on_push_*, on_unplug) on nodes before modifying links; these signals may veto operations by returning an error. Many operations assume the node is not already attached to another list; violating that assumption may lead to an inconsistent list (reported as ListBroken).

Fields

head: I

Head sentinel node ID.

tail: I

Tail sentinel node ID.

len: Cell<usize>

Number of nodes in the list (excluding sentinels).

Implementations

impl<I: IEntityListNodeID> EntityList<I>

pub fn new(alloc: &IDBoundAlloc<I>) -> Self

create a new empty list with head and tail sentinels linked with each other.

pub fn len(&self) -> usize

get the number of nodes in the list.

pub fn is_empty(&self) -> bool

check if the list is empty.

pub fn get_front_id(&self, alloc: &IDBoundAlloc<I>) -> Option<I>

try to get the front node ID, or None if the list is empty

pub fn get_back_id(&self, alloc: &IDBoundAlloc<I>) -> Option<I>

try to get the back node ID, or None if the list is empty

pub fn node_add_next( &self, node: I, new_node: I, alloc: &IDBoundAlloc<I>, ) -> EntityListRes<I>

Add a new node after an existing node linked to this list.

If the current node is linked to another list, then the operation is undefined. You’ll get a broken list without reporting an error.

Signal invocation

node_add_next will invoke on_push_next on node before modifying any links. If the signal returns an error, the operation is aborted without modifying any links.

pub fn node_add_prev( &self, node: I, new_node: I, alloc: &IDBoundAlloc<I>, ) -> EntityListRes<I>

Add a new node before an existing node linked to this list.

If the current node is linked to another list, then the operation is undefined. You’ll get a broken list without reporting an error.

Signal invocation

node_add_prev will invoke on_push_prev on node before modifying any links. If the signal returns an error, the operation is aborted without modifying any links.

pub fn node_unplug(&self, node: I, alloc: &IDBoundAlloc<I>) -> EntityListRes<I>

Unplug a node from the list.

Signal invocation

node_unplug will invoke on_unplug on node before modifying any links. If the signal returns an error, the operation is aborted without modifying any links.

pub fn push_back_id( &self, new_node: I, alloc: &IDBoundAlloc<I>, ) -> EntityListRes<I>

Push a new node to the back of the list.

pub fn push_front_id( &self, new_node: I, alloc: &IDBoundAlloc<I>, ) -> EntityListRes<I>

Push a new node to the front of the list.

pub fn pop_back(&self, alloc: &IDBoundAlloc<I>) -> EntityListRes<I, I>

Pop a node from the back of the list.

pub fn pop_front(&self, alloc: &IDBoundAlloc<I>) -> EntityListRes<I, I>

Pop a node from the front of the list.

pub fn get_range(&self, alloc: &IDBoundAlloc<I>) -> EntityListRange<I>

Get a range covering all nodes in the list (excluding sentinels).

pub fn get_range_with_sentinels(&self) -> EntityListRange<I>

Get a range covering all nodes in the list (including sentinels).

pub fn iter<'alloc>( &self, alloc: &'alloc IDBoundAlloc<I>, ) -> EntityListIter<'alloc, I>

Create an iterator over all nodes in the list (excluding sentinels).

pub fn iter_with_sentinels<'alloc>( &self, alloc: &'alloc IDBoundAlloc<I>, ) -> EntityListIter<'alloc, I>

Create an iterator over all nodes in the list (including sentinels).

pub fn forall_with_sentinel( &self, alloc: &IDBoundAlloc<I>, f: impl FnMut(I, &I::ObjectT) -> EntityListRes<I>, ) -> EntityListRes<I, ()>

Apply a function to all nodes in the list (including sentinels).