安全而且高效地完成*并发编程（concurrent programming）*是RUst 另一个主目标。并发编程（Concurrent programming），让不同的不同部分的程序相互独立运行，*并行编程（Parallel programing）*代码的不同部分同时执行，这两个概念随着计算在多处理器上利用越来越搞笑变得越来越重要。可惜，从古到今，并发和并行依然有困难以及时常有错误，Rust想改变这一点。
1 如何创建线程来同时运行不同的代码段 2
use std::thread;
fn main() {
let v = vec![1, 2, 3];
let handle = thread::spawn(|| {
println!("Here's a vector: {:?}", v);
});
handle.join().unwrap();
}$ cargo run
Compiling threads v0.1.0 (file:///projects/threads)
error[E0373]: closure may outlive the current function, but it borrows `v`, which is owned by the current function
--> src/main.rs:6:32
|
6 | let handle = thread::spawn(|| {
| ^^ may outlive borrowed value `v`
7 | println!("Here's a vector: {:?}", v);
| - `v` is borrowed here
|
note: function requires argument type to outlive `'static`
--> src/main.rs:6:18
|
6 | let handle = thread::spawn(|| {
| __________________^
7 | | println!("Here's a vector: {:?}", v);
8 | | });
| |______^
help: to force the closure to take ownership of `v` (and any other referenced variables), use the `move` keyword
|
6 | let handle = thread::spawn(move || {
| ^^^^^^^
error: aborting due to previous error
For more information about this error, try `rustc --explain E0373`.
error: could not compile `threads`.
To learn more, run the command again with --verbose.
use std::thread;
fn main() {
let v = vec![1, 2, 3];
let handle = thread::spawn(|| {
println!("Here's a vector: {:?}", v);
});
drop(v); // oh no!
handle.join().unwrap();
}有个越来越流行的用来保证并发安全的方式：消息传递(message passing)，线程或者使用者(actors)通过发送带有数据的消息来进行交流沟通。这个思想是来自 “Go 语言编程文档” 的slogan，不要通过共享内存来交换数据，用传递消息的是让来交换数据（Do not communicate by sharing memory; instead, share memory by communicating.）
Rust 实现消息传递的主要工具是 通道（channel）。