:mega: :mega: :mega: `kotlinx.coroutines` version ...

# coroutines

[Vsevolod Tolstopyatov [JB]]

📣 📣 📣 kotlinx.coroutines version 0.30.0.
We are happy to announce the last release for Kotlin 1.2.70 and the last 0.x.x release.
The next release will be 1.0.0-RC for Kotlin 1.3-RC and all deprecated API will be removed.

Changelist:
* [Major] async and async-like builders cancel parent on failure, making parallel decomposition completely exception-safe. No more unnecessary awaitAll in structured concurrency!
* [Major] Coroutine scheduler is used for Dispatchers.Default instead of deprecated CommonPool.
* Supervisor job and supervisor scope for more controlled cancellation of coroutines hierarchies.
* Job() with parent now also cancels parent on failure consistently with other scopes.
* Various bug fixes and improvements. See the full changelog here: https://github.com/Kotlin/kotlinx.coroutines/releases/tag/0.30.0.

To properly prepare your application to 1.0.0 release, do the following steps:
1) Update kotlinx.coroutines to 0.30.0 version.
2) Inspect compiler warnings about deprecated API and migrate it to a proposed alternative. Most of deprecated API has a corresponding replacement which can be applied from IDEA with quickfix.
3) Update Kotlin version to 1.3-RC and kotlinx.coroutines to 0.30.0-eap13.
4) Update kotlinx.coroutines to 1.0.0 when it’s released 🙂

Compatibility and migration policy: https://github.com/Kotlin/kotlinx.coroutines/blob/master/COMPATIBILITY.md

[Vsevolod Tolstopyatov [JB]]

0.30.0-eap13 will be released on Monday

[cbruegg]

One thing I was wondering: IIRC, it was discouraged in Kotlin to create an object singleton just for the sake of namespacing, while Dispatchers is doing pretty much that, right? Is there any specific reason behind the dispatchers not simply being top-level `val`s? (I'd actually be in favor of using `object`s for namespacing, but I don't want to violate style guides.)

[louiscad]

@cbruegg I'm not certain where you read/heard that. The stdlib itself uses this with Delegates

[cbruegg]

For instance @yole said it here: https://discuss.kotlinlang.org/t/best-practices-for-top-level-declarations/2198/3

[elizarov]

The decision was based on readability. There are many context elements and it is convenient to see that one is adding a dispatcher at a glance.