Struct Callback 

pub struct Callback<C, F, Params: SystemParam> {
    pub ctx: C,
    /* private fields */
}

Unified dispatch type. Stores per-callback context alongside pre-resolved resource access.

• Context-free handlers: Callback<(), CtxFree<F>, P> — created via IntoHandler::into_handler.
• Context-owning handlers: Callback<C, F, P> — created via IntoCallback::into_callback.

Both implement Handler<E>.

Examples

use nexus_rt::{WorldBuilder, ResMut, IntoCallback, Handler};

struct Ctx { count: u64 }

fn handler(ctx: &mut Ctx, mut val: ResMut<u64>, event: u32) {
    *val += event as u64;
    ctx.count += 1;
}

let mut builder = WorldBuilder::new();
builder.register::<u64>(0);
let mut world = builder.build();

let mut cb = handler.into_callback(Ctx { count: 0 }, world.registry_mut());
cb.run(&mut world, 10u32);

assert_eq!(cb.ctx.count, 1);
assert_eq!(*world.resource::<u64>(), 10);

Fields

ctx: C

Per-callback owned state. Accessible outside dispatch.

Trait Implementations

impl<C: 'static, E, F: FnMut(&mut C, E) + 'static> Handler<E> for Callback<C, F, ()>

fn run(&mut self, _world: &mut World, event: E)

Run this handler with the given event.

fn inputs_changed(&self, _world: &World) -> bool

Returns true if any input resource was modified this sequence.

fn name(&self) -> &'static str

Returns the handler’s name.

impl<C: 'static, E, F: 'static, P0: SystemParam + 'static> Handler<E> for Callback<C, F, (P0,)>

where for<'a> &'a mut F: FnMut(&mut C, P0, E) + FnMut(&mut C, P0::Item<'a>, E),

fn run(&mut self, world: &mut World, event: E)

Run this handler with the given event.

fn inputs_changed(&self, world: &World) -> bool

Returns true if any input resource was modified this sequence.

fn name(&self) -> &'static str

Returns the handler’s name.

impl<C: 'static, E, F: 'static, P0: SystemParam + 'static, P1: SystemParam + 'static> Handler<E> for Callback<C, F, (P0, P1)>

where for<'a> &'a mut F: FnMut(&mut C, P0, P1, E) + FnMut(&mut C, P0::Item<'a>, P1::Item<'a>, E),

fn run(&mut self, world: &mut World, event: E)

Run this handler with the given event.

fn inputs_changed(&self, world: &World) -> bool

Returns true if any input resource was modified this sequence.

fn name(&self) -> &'static str

Returns the handler’s name.

impl<C: 'static, E, F: 'static, P0: SystemParam + 'static, P1: SystemParam + 'static, P2: SystemParam + 'static> Handler<E> for Callback<C, F, (P0, P1, P2)>

where for<'a> &'a mut F: FnMut(&mut C, P0, P1, P2, E) + FnMut(&mut C, P0::Item<'a>, P1::Item<'a>, P2::Item<'a>, E),

fn run(&mut self, world: &mut World, event: E)

Run this handler with the given event.

fn inputs_changed(&self, world: &World) -> bool

Returns true if any input resource was modified this sequence.

fn name(&self) -> &'static str

Returns the handler’s name.

impl<C: 'static, E, F: 'static, P0: SystemParam + 'static, P1: SystemParam + 'static, P2: SystemParam + 'static, P3: SystemParam + 'static> Handler<E> for Callback<C, F, (P0, P1, P2, P3)>

where for<'a> &'a mut F: FnMut(&mut C, P0, P1, P2, P3, E) + FnMut(&mut C, P0::Item<'a>, P1::Item<'a>, P2::Item<'a>, P3::Item<'a>, E),

fn run(&mut self, world: &mut World, event: E)

Run this handler with the given event.

fn inputs_changed(&self, world: &World) -> bool

Returns true if any input resource was modified this sequence.

fn name(&self) -> &'static str

Returns the handler’s name.

impl<C: 'static, E, F: 'static, P0: SystemParam + 'static, P1: SystemParam + 'static, P2: SystemParam + 'static, P3: SystemParam + 'static, P4: SystemParam + 'static> Handler<E> for Callback<C, F, (P0, P1, P2, P3, P4)>

where for<'a> &'a mut F: FnMut(&mut C, P0, P1, P2, P3, P4, E) + FnMut(&mut C, P0::Item<'a>, P1::Item<'a>, P2::Item<'a>, P3::Item<'a>, P4::Item<'a>, E),

fn run(&mut self, world: &mut World, event: E)

Run this handler with the given event.

fn inputs_changed(&self, world: &World) -> bool

Returns true if any input resource was modified this sequence.

fn name(&self) -> &'static str

Returns the handler’s name.

impl<C: 'static, E, F: 'static, P0: SystemParam + 'static, P1: SystemParam + 'static, P2: SystemParam + 'static, P3: SystemParam + 'static, P4: SystemParam + 'static, P5: SystemParam + 'static> Handler<E> for Callback<C, F, (P0, P1, P2, P3, P4, P5)>

where for<'a> &'a mut F: FnMut(&mut C, P0, P1, P2, P3, P4, P5, E) + FnMut(&mut C, P0::Item<'a>, P1::Item<'a>, P2::Item<'a>, P3::Item<'a>, P4::Item<'a>, P5::Item<'a>, E),

fn run(&mut self, world: &mut World, event: E)

Run this handler with the given event.

fn inputs_changed(&self, world: &World) -> bool

Returns true if any input resource was modified this sequence.

fn name(&self) -> &'static str

Returns the handler’s name.

impl<C: 'static, E, F: 'static, P0: SystemParam + 'static, P1: SystemParam + 'static, P2: SystemParam + 'static, P3: SystemParam + 'static, P4: SystemParam + 'static, P5: SystemParam + 'static, P6: SystemParam + 'static> Handler<E> for Callback<C, F, (P0, P1, P2, P3, P4, P5, P6)>

where for<'a> &'a mut F: FnMut(&mut C, P0, P1, P2, P3, P4, P5, P6, E) + FnMut(&mut C, P0::Item<'a>, P1::Item<'a>, P2::Item<'a>, P3::Item<'a>, P4::Item<'a>, P5::Item<'a>, P6::Item<'a>, E),

fn run(&mut self, world: &mut World, event: E)

Run this handler with the given event.

fn inputs_changed(&self, world: &World) -> bool

Returns true if any input resource was modified this sequence.

fn name(&self) -> &'static str

Returns the handler’s name.

impl<C: 'static, E, F: 'static, P0: SystemParam + 'static, P1: SystemParam + 'static, P2: SystemParam + 'static, P3: SystemParam + 'static, P4: SystemParam + 'static, P5: SystemParam + 'static, P6: SystemParam + 'static, P7: SystemParam + 'static> Handler<E> for Callback<C, F, (P0, P1, P2, P3, P4, P5, P6, P7)>

where for<'a> &'a mut F: FnMut(&mut C, P0, P1, P2, P3, P4, P5, P6, P7, E) + FnMut(&mut C, P0::Item<'a>, P1::Item<'a>, P2::Item<'a>, P3::Item<'a>, P4::Item<'a>, P5::Item<'a>, P6::Item<'a>, P7::Item<'a>, E),

fn run(&mut self, world: &mut World, event: E)

Run this handler with the given event.

fn inputs_changed(&self, world: &World) -> bool

Returns true if any input resource was modified this sequence.

fn name(&self) -> &'static str

Returns the handler’s name.