Struct shred::ParSeq

pub struct ParSeq<P, T> { /* private fields */ }

A dispatcher intended to be used with Par and Seq structures.

This is more flexible and performant than Dispatcher, however, you have to check conflicts yourself. That means you cannot run two systems in parallel which write to the same resource; if you’d do that, one of the systems will panic while trying to fetch the SystemData.

Thread-local systems

This dispatcher also allows more freedom for thread-local systems; you can execute wherever you want, just not in parallel with other systems (putting one inside par! will give you a compile-time error saying the Send requirement is unmet).

Examples

#[macro_use(par, seq)]
extern crate shred;


let x = 5u8;

let mut dispatcher = ParSeq::new(
    seq![
        par![SysA, SysWithLifetime(&x), seq![SysC, SysD,],],
        SysB,
        SysLocal(&x as *const u8),
    ],
    &pool,
);

dispatcher.dispatch(&mut world);

Implementations

impl<P, T> ParSeq<P, T>

where P: Borrow<ThreadPool>, T: for<'a> RunWithPool<'a>,

pub fn new(run: T, pool: P) -> Self

Creates a new ParSeq dispatcher. run is usually created by using the par! / seq! macros.

pub fn setup(&mut self, world: &mut World)

Sets up world for dispatching. This will add default values for required resources by calling System::setup.

pub fn dispatch(&mut self, world: &World)

Dispatches the systems using world. This doesn’t call any virtual functions.

Please note that this method assumes that no resource is currently borrowed. If that’s the case, it panics.

Trait Implementations

impl<'a, P, T> RunNow<'a> for ParSeq<P, T>

where P: Borrow<ThreadPool>, T: for<'b> RunWithPool<'b>,

fn run_now(&mut self, world: &World)

Runs the system now.

fn setup(&mut self, world: &mut World)

Sets up World for a later call to run_now.

fn dispose(self: Box<Self>, world: &mut World)

Performs clean up that requires resources from the World. This commonly removes components from world which depend on external resources.