Struct Has

pub struct Has<Q> { /* private fields */ }

A Query which contains a boolean indicating whether the query Q matches.

Like With, Has does not provide access to the data returned by Q.

Implementations

impl<Q> Has<Q>

pub const fn new(has: bool) -> Has<Q>

Creates a new instance wrapping has.

pub const fn get(self) -> bool

Extracts the inner boolean.

Trait Implementations

impl<Q> Clone for Has<Q>

fn clone(&self) -> Has<Q>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<Q> Debug for Has<Q>

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

Formats the value using the given formatter.

impl<Q> Default for Has<Q>

fn default() -> Has<Q>

Returns the “default value” for a type.

impl<Q> Deref for Has<Q>

type Target = bool

The resulting type after dereferencing.

fn deref(&self) -> &<Has<Q> as Deref>::Target

Dereferences the value.

impl<Q> DerefMut for Has<Q>

fn deref_mut(&mut self) -> &mut <Has<Q> as Deref>::Target

Mutably dereferences the value.

impl<Q> Hash for Has<Q>

fn hash<H>(&self, state: &mut H)

where H: Hasher,

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl<Q> Ord for Has<Q>

fn cmp(&self, other: &Has<Q>) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl<Q> PartialEq for Has<Q>

fn eq(&self, other: &Has<Q>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<Q> PartialOrd for Has<Q>

fn partial_cmp(&self, other: &Has<Q>) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<Q> Query for Has<Q>

where Q: Query,

type Item<'a> = Has<Q>

The item returned by this query. This is usually the same type as Self, but with a modified lifetime.

type ArchState = bool

Per-archetype state, e.g. pointers to archetype columns.

type State = <Q as Query>::State

Cached data for fetch initialization, e.g. component indices.

fn init( world: &mut World, config: &mut HandlerConfig, ) -> Result<(ComponentAccess, <Has<Q> as Query>::State), InitError>

Initialize the query. Returns an expression describing the components accessed by the query and a new instance of Self::State.

fn new_state(world: &mut World) -> <Has<Q> as Query>::State

Returns a new Self::State instance.

fn new_arch_state( arch: &Archetype, state: &mut <Has<Q> as Query>::State, ) -> Option<<Has<Q> as Query>::ArchState>

Returns a new Self::ArchState instance.

unsafe fn get<'a>( state: &<Has<Q> as Query>::ArchState, _row: ArchetypeRow, ) -> <Has<Q> as Query>::Item<'a>

Gets the query item at the given row in the archetype.

impl<Q> Copy for Has<Q>

impl<Q> Eq for Has<Q>

impl<Q> ReadOnlyQuery for Has<Q>

where Q: Query,