Function button

src/timely-util/src/builder_async.rs:726–747

Creates a new coordinated button the worker configuration described by `scope`.

(
    scope: Scope<'scope, T>,
    addr: Rc<[usize]>,
)

/// Creates a new coordinated button the worker configuration described by `scope`.
pub fn button<'scope, T: Timestamp>(
    scope: Scope<'scope, T>,
    addr: Rc<[usize]>,
) -> (ButtonHandle, Button) {
    let index = scope.worker().new_identifier();
    let (pushers, puller) = scope.worker().allocate(index, addr);

    let local_pressed = Rc::new(Cell::new(false));

    let handle = ButtonHandle {
        buttons_remaining: scope.peers(),
        local_pressed: Rc::clone(&local_pressed),
        puller,
    };

    let token = Button {
        pushers,
        local_pressed,
    };

    (handle, token)
}

/// A button that can be used to coordinate an action after all workers have pressed it.
pub struct ButtonHandle {