From a6ebd26208f9be1a34b2a4cb8bf7b89badebd15c Mon Sep 17 00:00:00 2001
From: Jake Goulding <jake.goulding@gmail.com>
Date: Sun, 8 Mar 2015 16:09:09 -0400
Subject: [PATCH 1/2] Update example that uses deprecated Thread::scoped
---
src/doc/intro.md | 18 +++++++++---------
1 file changed, 9 insertions(+), 9 deletions(-)
diff --git a/src/doc/intro.md b/src/doc/intro.md
index bb86de64e7a..3e5b8ec6bef 100644
--- a/src/doc/intro.md
+++ b/src/doc/intro.md
@@ -389,11 +389,11 @@ safe concurrent programs.
Here's an example of a concurrent Rust program:
```{rust}
-use std::thread::Thread;
+use std::thread;
fn main() {
let guards: Vec<_> = (0..10).map(|_| {
- Thread::scoped(|| {
+ thread::scoped(|| {
println!("Hello, world!");
})
}).collect();
@@ -421,13 +421,13 @@ problem.
Let's see an example. This Rust code will not compile:
```{rust,ignore}
-use std::thread::Thread;
+use std::thread;
fn main() {
let mut numbers = vec![1, 2, 3];
let guards: Vec<_> = (0..3).map(|i| {
- Thread::scoped(move || {
+ thread::scoped(move || {
numbers[i] += 1;
println!("numbers[{}] is {}", i, numbers[i]);
});
@@ -439,7 +439,7 @@ It gives us this error:
```text
7:25: 10:6 error: cannot move out of captured outer variable in an `FnMut` closure
-7 Thread::scoped(move || {
+7 thread::scoped(move || {
8 numbers[i] += 1;
9 println!("numbers[{}] is {}", i, numbers[i]);
10 });
@@ -471,7 +471,7 @@ mutation doesn't cause a data race.
Here's what using an Arc with a Mutex looks like:
```{rust}
-use std::thread::Thread;
+use std::thread;
use std::sync::{Arc,Mutex};
fn main() {
@@ -479,7 +479,7 @@ fn main() {
let guards: Vec<_> = (0..3).map(|i| {
let number = numbers.clone();
- Thread::scoped(move || {
+ thread::scoped(move || {
let mut array = number.lock().unwrap();
array[i] += 1;
println!("numbers[{}] is {}", i, array[i]);
@@ -535,13 +535,13 @@ As an example, Rust's ownership system is _entirely_ at compile time. The
safety check that makes this an error about moved values:
```{rust,ignore}
-use std::thread::Thread;
+use std::thread;
fn main() {
let numbers = vec![1, 2, 3];
let guards: Vec<_> = (0..3).map(|i| {
- Thread::scoped(move || {
+ thread::scoped(move || {
println!("{}", numbers[i]);
});
}).collect();
From b426a242e3da27e9a407f9f896bcb86d347f76d1 Mon Sep 17 00:00:00 2001
From: Jake Goulding <jake.goulding@gmail.com>
Date: Sun, 8 Mar 2015 16:10:19 -0400
Subject: [PATCH 2/2] Make concurrent examples actually run concurrently
If we end the `scoped` call with a semicolon, the `JoinGuard` will be
dropped and not returned from the `map`. The thread will start up and
we immediately block, making for a very expensive sequential loop.
---
src/doc/intro.md | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/src/doc/intro.md b/src/doc/intro.md
index 3e5b8ec6bef..9e575abeee2 100644
--- a/src/doc/intro.md
+++ b/src/doc/intro.md
@@ -430,7 +430,7 @@ fn main() {
thread::scoped(move || {
numbers[i] += 1;
println!("numbers[{}] is {}", i, numbers[i]);
- });
+ })
}).collect();
}
```
@@ -442,7 +442,7 @@ It gives us this error:
7 thread::scoped(move || {
8 numbers[i] += 1;
9 println!("numbers[{}] is {}", i, numbers[i]);
-10 });
+10 })
error: aborting due to previous error
```
@@ -483,7 +483,7 @@ fn main() {
let mut array = number.lock().unwrap();
array[i] += 1;
println!("numbers[{}] is {}", i, array[i]);
- });
+ })
}).collect();
}
```
@@ -543,7 +543,7 @@ fn main() {
let guards: Vec<_> = (0..3).map(|i| {
thread::scoped(move || {
println!("{}", numbers[i]);
- });
+ })
}).collect();
}
```