Struct shred::Resources

pub struct Resources { /* fields omitted */ }

A resource container, which provides methods to access to the contained resources.

Resource Ids

Resources are in general identified by ResourceId, which consists of a TypeId and a usize. The usize may be used as an additional identifier. In many cases, there are convenience methods which assume this id is 0.

Methods

impl Resources

pub fn new() -> Self

Creates a new, empty resource container.

pub fn add<R>(&mut self, r: R) where
    R: Resource, 

Adds a new resource to this container.

This method calls add_with_id with 0 for the id.

Panics

Panics if the resource is already registered.

Examples

Every type satisfying Any + Debug + Send + Sync automatically implements Resource:

#[derive(Debug)]
struct MyRes(i32);

When you have a resource, simply register it like this:

use shred::Resources;

let mut res = Resources::new();
res.add(MyRes(5));

pub fn add_with_id<R>(&mut self, r: R, id: usize) where
    R: Resource, 

Like add(), but allows specifying and id while add() assumes 0.

pub fn has_value(&self, res_id: ResourceId) -> bool

Returns true if the specified type / id combination is registered.

pub fn entry<R>(&mut self) -> Entry<R> where
    R: Resource, 

Returns an entry for the resource with type R and id 0.

pub fn fetch<T>(&self, id: usize) -> Fetch<T> where
    T: Resource, 

Fetches the resource with the specified type T. The id is useful if you don't define your resources in Rust or you want a more dynamic resource handling. By default, the #[derive(SystemData)] passes () as id.

Panics

Panics if the resource is being accessed mutably. Also panics if there is no such resource.

pub fn try_fetch<T>(&self, id: usize) -> Option<Fetch<T>> where
    T: Resource, 

Like fetch, but returns an Option instead of panicking in the case of the resource being accessed mutably.

pub fn fetch_mut<T>(&self, id: usize) -> FetchMut<T> where
    T: Resource, 

Fetches the resource with the specified type T mutably.

Please see fetch for details.

pub fn try_fetch_mut<T>(&self, id: usize) -> Option<FetchMut<T>> where
    T: Resource, 

Like fetch_mut, but returns an Option instead of panicking in the case of the resource being accessed mutably.

pub fn fetch_id(&self, id: TypeId, comp_id: usize) -> FetchId

Fetches the resource with the specified type id.

Please see fetch for details.

Panics

Panics if no resource with the id exists.

pub fn try_fetch_id(&self, id: TypeId, comp_id: usize) -> Option<FetchId>

Like fetch_id, but returns an Option rather than panicking.

pub fn fetch_id_mut(&self, id: TypeId, comp_id: usize) -> FetchIdMut

Fetches the resource with the specified type id mutably.

Please see fetch for details.

Panics

Panics if no resource with the id exists.

pub fn try_fetch_id_mut(&self, id: TypeId, comp_id: usize) -> Option<FetchIdMut>

Like fetch_id_mut, but returns an Option rather than panicking.

Trait Implementations

impl Default for Resources

fn default() -> Resources

Returns the "default value" for a type.