Struct Archetypes 

pub struct Archetypes {
    archetypes: Vec<Archetype>,
    by_types: HashMap<Box<[TypeId]>, u32>,
}

Every archetype of a world.

Fields

archetypes: Vec<Archetype>

by_types: HashMap<Box<[TypeId]>, u32>

Implementations

impl Archetypes

pub(crate) fn new() -> Self

A pool containing only the empty archetype.

pub(crate) fn find_with<T>( &self, types: T, is_match: impl FnMut(&[TypeId]) -> bool, ) -> Option<u32>

where T: ExactSizeIterator<Item = TypeId>,

The id of the archetype whose types are types as is_match reads them, or None when no such archetype is registered.

This is the allocation-free lookup: the type sequence is hashed as it is iterated and compared in place, so a caller that holds the types apart rather than in one slice builds no key for a hit. The hash comes from the map’s own hasher, so it always agrees with how the stored keys were hashed.

Relies on hashbrown’s raw-entry feature: without it this does not compile rather than silently missing every lookup.

pub(crate) fn register(&mut self, archetype: Archetype) -> u32

Register a freshly built archetype and return its id.

pub fn get(&self, id: u32) -> Result<&Archetype, ArchetypeAccessError>

The archetype with this id.

An id is only minted when an archetype is registered, so an id that names nothing came from another world or from arithmetic on a u32; either way it answers ArchetypeAccessError::NoSuchArchetype rather than quietly naming no archetype.

pub(crate) fn get_mut( &mut self, id: u32, ) -> Result<&mut Archetype, ArchetypeAccessError>

The archetype with this id, mutably. See Archetypes::get.

pub fn as_slice(&self) -> &[Archetype]

Every archetype, as a slice.

An archetype’s id is its position in this slice, which is what crate::Location::archetype and Archetype::names are read against.

Trait Implementations

impl Debug for Archetypes

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

Reports the number of archetypes, not the archetypes themselves.