Struct ComponentRegistry 

pub struct ComponentRegistry { /* private fields */ }

A registry that maps component types to their semantic domains.

This is a critical internal part of the World. It provides a single source of truth for determining which semantic group a component’s data belongs to, enabling the World to correctly store and retrieve component data from pages.

Implementations

impl ComponentRegistry

pub fn get_domain(&self, type_id: TypeId) -> Option<SemanticDomain>

Looks up the SemanticDomain for a given TypeId.

pub fn layout_of(&self, type_id: TypeId) -> Option<LayoutPolicy>

Returns the LayoutPolicy a component is currently stored with.

pub fn set_layout(&mut self, type_id: TypeId, layout: LayoutPolicy)

Sets the intended LayoutPolicy for a component. The actual repack of stored columns is performed by the layout-adaptation pass; this only records the target.

pub fn record_access(&self, type_ids: &[TypeId], rows: u64)

Records one access: increments the query count and adds rows to the scanned total for every component in type_ids. Lock-free, called once per query — never per element.

pub fn access_stats(&self, type_id: TypeId) -> Option<(u64, u64)>

Returns (query_count, rows_scanned) for a component, if registered.

pub fn size_of(&self, type_id: TypeId) -> Option<usize>

size_of for a registered component type, or None if unregistered.

pub fn access_snapshot(&self) -> Vec<(TypeId, usize, u64, u64)>

Snapshot of every registered component’s (type_id, size_bytes, query_count, rows_scanned) — the input the DCC’s layout advisor reads (read-only; observation tunnel). Allocates a small Vec (one entry per component type), so it is cheap enough to sample off the hot path.

Trait Implementations

impl Debug for ComponentRegistry

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

Formats the value using the given formatter.

impl Default for ComponentRegistry

fn default() -> ComponentRegistry

Returns the “default value” for a type.