1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
//! **Sh**ared **re**source **d**ispatcher
//!
//! This library allows to dispatch
//! systems, which can have interdependencies,
//! shared and exclusive resource access, in parallel.
//!
//! # Examples
//!
//! ```rust
//! extern crate shred;
//!
//! use shred::{DispatcherBuilder, Read, Resource, ResourceId, System, SystemData, World, Write};
//!
//! #[derive(Debug, Default)]
//! struct ResA;
//!
//! #[derive(Debug, Default)]
//! struct ResB;
//!
//! # #[cfg(feature = "shred-derive")]
//! #[derive(SystemData)] // Provided with `shred-derive` feature
//! struct Data<'a> {
//!     a: Read<'a, ResA>,
//!     b: Write<'a, ResB>,
//! }
//!
//! struct EmptySystem;
//!
//! impl<'a> System<'a> for EmptySystem {
//!     type SystemData = Data<'a>;
//!
//!     fn run(&mut self, bundle: Data<'a>) {
//!         println!("{:?}", &*bundle.a);
//!         println!("{:?}", &*bundle.b);
//!     }
//! }
//!
//! let mut world = World::empty();
//! let mut dispatcher = DispatcherBuilder::new()
//!     .with(EmptySystem, "empty", &[])
//!     .build();
//! world.insert(ResA);
//! world.insert(ResB);
//!
//! dispatcher.dispatch(&mut world);
//! #
//! # // The following is required for the snippet to compile without the `shred-derive` feature.
//! #
//! # #[cfg(not(feature = "shred-derive"))]
//! # struct Data<'a> {
//! #     a: Read<'a, ResA>,
//! #     b: Write<'a, ResB>,
//! # }
//! #
//! # #[cfg(not(feature = "shred-derive"))]
//! # impl<'a> SystemData<'a> for Data<'a> {
//! #     fn setup(world: &mut World) {
//! #         Read::<'_, ResA>::setup(world);
//! #         Write::<'_, ResB>::setup(world);
//! #     }
//! #
//! #     fn fetch(world: &'a World) -> Self {
//! #         Self {
//! #             a: Read::<'_, ResA>::fetch(world),
//! #             b: Write::<'_, ResB>::fetch(world),
//! #         }
//! #     }
//! #
//! #     fn reads() -> Vec<ResourceId> {
//! #         Read::<'_, ResA>::reads()
//! #     }
//! #
//! #     fn writes() -> Vec<ResourceId> {
//! #         Write::<'_, ResB>::writes()
//! #     }
//! # }
//! ```
//!
//! Once you are more familiar with how system data and parallelization works,
//! you can take look at a more flexible and performant way to dispatch:
//! `ParSeq`. Using it is bit trickier, but it allows dispatching without any
//! virtual function calls.

#![deny(unused_must_use, clippy::disallowed_types)]
#![warn(missing_docs)]

pub mod cell;

mod dispatch;
mod meta;
mod system;
mod world;

/// A reexport of the `#[derive(SystemData]` macro provided by `shred-derive`.
/// This requires that the `shred-derive` feature is enabled.
#[cfg(feature = "shred-derive")]
pub use shred_derive::SystemData;

#[cfg(feature = "parallel")]
pub use crate::dispatch::AsyncDispatcher;
#[cfg(feature = "parallel")]
pub use crate::dispatch::{Par, ParSeq, RunWithPool, Seq};
pub use crate::{
    dispatch::{
        BatchAccessor, BatchController, BatchUncheckedWorld, Dispatcher, DispatcherBuilder,
        MultiDispatchController, MultiDispatcher,
    },
    meta::{CastFrom, MetaIter, MetaIterMut, MetaTable},
    system::{
        Accessor, AccessorCow, DynamicSystemData, RunNow, RunningTime, StaticAccessor, System,
        SystemData,
    },
    world::{
        DefaultProvider, Entry, Fetch, FetchMut, PanicHandler, Read, ReadExpect, Resource,
        ResourceId, SetupHandler, World, Write, WriteExpect,
    },
};

/// Alias for `World` for easier migration to the new version. Will be removed
/// in the future.
#[deprecated(since = "0.8.0", note = "renamed to `World`")]
pub type Resources = World;