This looks like the most logical target to give to this link, or at least what I would expect as someone that want to integrate with a native library.
r? @steveklabnik
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.
The failing concurrency example was doing something different from the
working example. This commit changes just enough of the failing example
to (1) still fail with the same error, (2) tries to do the same as the
working example (increment a vector value and print it).
r? @steveklabnik
Replace deprecated integer suffixes. Remove integer type notations
altogether where possible. Replace uses of deprecated `range()`
function with range notation.
* Use range notation instead of deprecated `range()`
* Remove deprecated `u` integer suffixes used in ranges
* Replace deprecated `i` integer suffixes with `is` for vector numbers
`Thread::spawn()` still gives "use of unstable item" warning which I
hadn't found a way to fix.
- Make punctuation/formatting consistent with the changes made to *The Rust Programming Language* in #20782.
- Use title casing for "Safety and Speed" section.
- Reword some phrases to improve clarity.
- Make punctuation/formatting consistent with the changes made to "The
Rust Programming Language" in #20782.
- Use title casing for "Safety and Speed" section.
- Reword some phrases to improve clarity.
Compiler gives the following warning:
`warning: the `u` suffix on integers is deprecated; use `us` or one of the fixed-sized suffixes`
And also the errror:
`error: mismatched types: expected `u64`, found `usize` (expected u64, found usize)`
Changing the suffix to `u64` results in a successful `cargo run` outputting the desired `Versions compared successfully!`
This pulls all of our long-form documentation into a single document,
nicknamed "the book" and formally titled "The Rust Programming
Language."
A few things motivated this change:
* People knew of The Guide, but not the individual Guides. This merges
them together, helping discoverability.
* You can get all of Rust's longform documentation in one place, which
is nice.
* We now have rustbook in-tree, which can generate this kind of
documentation. While its style is basic, the general idea is much
better: a table of contents on the left-hand side.
* Rather than a almost 10,000-line guide.md, there are now smaller files
per section.
All of the current std::sync primitives have poisoning enable which means that
when a task fails inside of a write-access lock then all future attempts to
acquire the lock will fail. This strategy ensures that stale data whose
invariants are possibly not upheld are never viewed by other tasks to help
propagate unexpected panics (bugs in a program) among tasks.
Currently there is no way to test whether a mutex or rwlock is poisoned. One
method would be to duplicate all the methods with a sister foo_catch function,
for example. This pattern is, however, against our [error guidelines][errors].
As a result, this commit exposes the fact that a task has failed internally
through the return value of a `Result`.
[errors]: https://github.com/rust-lang/rfcs/blob/master/text/0236-error-conventions.md#do-not-provide-both-result-and-fail-variants
All methods now return a `LockResult<T>` or a `TryLockResult<T>` which
communicates whether the lock was poisoned or not. In a `LockResult`, both the
`Ok` and `Err` variants contains the `MutexGuard<T>` that is being returned in
order to allow access to the data if poisoning is not desired. This also means
that the lock is *always* held upon returning from `.lock()`.
A new type, `PoisonError`, was added with one method `into_guard` which can
consume the assertion that a lock is poisoned to gain access to the underlying
data.
This is a breaking change because the signatures of these methods have changed,
often incompatible ways. One major difference is that the `wait` methods on a
condition variable now consume the guard and return it in as a `LockResult` to
indicate whether the lock was poisoned while waiting. Most code can be updated
by calling `.unwrap()` on the return value of `.lock()`.
[breaking-change]
This commit is part of a series that introduces a `std::thread` API to
replace `std::task`.
In the new API, `spawn` returns a `JoinGuard`, which by default will
join the spawned thread when dropped. It can also be used to join
explicitly at any time, returning the thread's result. Alternatively,
the spawned thread can be explicitly detached (so no join takes place).
As part of this change, Rust processes now terminate when the main
thread exits, even if other detached threads are still running, moving
Rust closer to standard threading models. This new behavior may break code
that was relying on the previously implicit join-all.
In addition to the above, the new thread API also offers some built-in
support for building blocking abstractions in user space; see the module
doc for details.
Closes#18000
[breaking-change]