Struct Entry 

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

A component value along with its entity’s id and change tracking information.

An entry is returned from component queries. It is a wrapper around a component that provides extra information about the last time the component was modified.

Entry implements Deref and DerefMut, but you can also obtain a reference to the component value through Entry::value or Entry::value_mut.

let mut world = World::default();
let e = world.get_entities_mut().create();
let cs = world.get_components_mut();
cs.insert_bundle(*e, (123, "123", 123.0));
let mut query = cs.query::<(&mut i32, &f64)>();
let (entry_i32, entry_f64): (&mut Entry<i32>, &Entry<f64>) = query.find_one(e.id()).unwrap();
**entry_i32 = 321;
assert_eq!(321 - 123, **entry_i32 - **entry_f64 as i32);
// both components were added (and one component modified) this iteration
assert_eq!(entry_i32.last_changed(), entry_f64.last_changed());

Implementations

impl<T> Entry<T>

pub fn new(id: usize, value: T) -> Self

pub fn id(&self) -> usize

Get the identifier of the entity this component is associated with.

pub fn value(&self) -> &T

Get a reference to the component value.

pub fn value_mut(&mut self) -> &mut T

Get a mutable reference to the component value.

This updates the last time this copmonent was changed.

pub fn into_inner(self) -> T

pub fn has_changed_since(&self, iteration: u64) -> bool

Determine if the component has changed since the given iteration timestamp.

This includes being added or being modified.

pub fn has_changed_after(&self, iteration: u64) -> bool

Determine if the component has changed after the given iteration timestamp.

This includes being added or being modified.

pub fn was_added_since(&self, iteration: u64) -> bool

Determine if the component has been added since the given iteration timestamp.

pub fn was_added_after(&self, iteration: u64) -> bool

Determine if the component was added after the given iteration timestamp.

pub fn was_modified_since(&self, iteration: u64) -> bool

Determine if the component has been modified since the given iteration timestamp, but has not been added.

pub fn was_modified_after(&self, iteration: u64) -> bool

Determine if the component has been modified after the given iteration timestamp, but has not been added.

pub fn last_changed(&self) -> u64

Return the last time this component was changed.

Trait Implementations

impl<T> AsRef<T> for Entry<T>

fn as_ref(&self) -> &T

Converts this type into a shared reference of the (usually inferred) input type.

impl<T: Clone> Clone for Entry<T>

fn clone(&self) -> Entry<T>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<T: Debug> Debug for Entry<T>

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

Formats the value using the given formatter.

impl<T> Deref for Entry<T>

type Target = T

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl<T> DerefMut for Entry<T>

fn deref_mut(&mut self) -> &mut Self::Target

Mutably dereferences the value.

impl<T: PartialEq> PartialEq for Entry<T>

fn eq(&self, other: &Entry<T>) -> 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<T> StructuralPartialEq for Entry<T>