Struct RequiredResource 

pub struct RequiredResource {
    pub name: &'static str,
    pub type_id: TypeId,
    pub present: fn(&World, &Resources) -> bool,
    pub hint: Option<&'static str>,
}

A resource requirement declared by a SystemParam/System, carrying a human-readable name, the resource’s TypeId (so App can check it against RequiredResources — resources some plugin has declared it eventually provides, e.g. an async GPU backend or a LazyResource — and a way to check presence dynamically (needed because System::requires is type-erased — the concrete T is only known where the check is constructed, inside each SystemParam impl).

Fields

name: &'static str

type_id: TypeId

present: fn(&World, &Resources) -> bool

hint: Option<&'static str>

Overrides App’s generic “call app.provides::<T>() or App::add_resource” advice when this resource has its own, more specific registration path (e.g. Events<T> — the actual fix is app.add_event::<T>(), not a manual provides call). None falls back to the generic advice, appropriate for a plain Res<T>/ResMut<T> on an arbitrary user resource type.

Trait Implementations

impl Clone for RequiredResource

fn clone(&self) -> RequiredResource

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for RequiredResource