mirror of
https://github.com/tokio-rs/tokio.git
synced 2026-08-17 00:00:11 +02:00
68 lines
2.8 KiB
Rust
68 lines
2.8 KiB
Rust
#![doc(html_root_url = "https://docs.rs/tokio-executor/0.1.7")]
|
|
#![deny(missing_docs, missing_debug_implementations, rust_2018_idioms)]
|
|
#![cfg_attr(test, deny(warnings))]
|
|
#![doc(test(no_crate_inject, attr(deny(rust_2018_idioms))))]
|
|
|
|
//! Task execution related traits and utilities.
|
|
//!
|
|
//! In the Tokio execution model, futures are lazy. When a future is created, no
|
|
//! work is performed. In order for the work defined by the future to happen,
|
|
//! the future must be submitted to an executor. A future that is submitted to
|
|
//! an executor is called a "task".
|
|
//!
|
|
//! The executor is responsible for ensuring that [`Future::poll`] is called
|
|
//! whenever the task is notified. Notification happens when the internal
|
|
//! state of a task transitions from *not ready* to *ready*. For example, a
|
|
//! socket might have received data and a call to `read` will now be able to
|
|
//! succeed.
|
|
//!
|
|
//! This crate provides traits and utilities that are necessary for building an
|
|
//! executor, including:
|
|
//!
|
|
//! * The [`Executor`] trait spawns future object onto an executor.
|
|
//!
|
|
//! * The [`TypedExecutor`] trait spawns futures of a specific type onto an
|
|
//! executor. This is used to be generic over executors that spawn futures
|
|
//! that are either `Send` or `!Send` or implement executors that apply to
|
|
//! specific futures.
|
|
//!
|
|
//! * [`enter`] marks that the current thread is entering an execution
|
|
//! context. This prevents a second executor from accidentally starting from
|
|
//! within the context of one that is already running.
|
|
//!
|
|
//! * [`DefaultExecutor`] spawns tasks onto the default executor for the current
|
|
//! context.
|
|
//!
|
|
//! * [`Park`] abstracts over blocking and unblocking the current thread.
|
|
//!
|
|
//! # Implementing an executor
|
|
//!
|
|
//! Executors should always implement `TypedExecutor`. This usually is the bound
|
|
//! that applications and libraries will use when generic over an executor. See
|
|
//! the [trait documentation][`TypedExecutor`] for more details.
|
|
//!
|
|
//! If the executor is able to spawn all futures that are `Send`, then the
|
|
//! executor should also implement the `Executor` trait. This trait is rarely
|
|
//! used directly by applications and libraries. Instead, `tokio::spawn` is
|
|
//! configured to dispatch to type that implements `Executor`.
|
|
//!
|
|
//! [`Executor`]: trait.Executor.html
|
|
//! [`TypedExecutor`]: trait.TypedExecutor.html
|
|
//! [`enter`]: fn.enter.html
|
|
//! [`DefaultExecutor`]: struct.DefaultExecutor.html
|
|
//! [`Park`]: park/index.html
|
|
//! [`Future::poll`]: https://docs.rs/futures/0.1/futures/future/trait.Future.html#tymethod.poll
|
|
|
|
mod enter;
|
|
mod error;
|
|
mod executor;
|
|
mod global;
|
|
pub mod park;
|
|
mod typed;
|
|
|
|
pub use crate::enter::{enter, Enter, EnterError};
|
|
pub use crate::error::SpawnError;
|
|
pub use crate::executor::Executor;
|
|
pub use crate::global::{spawn, with_default, DefaultExecutor};
|
|
pub use crate::typed::TypedExecutor;
|