Feature #18256
Updated by Eregon (Benoit Daloze) about 3 years ago
Currently these 4 classes are defined as both constants of `Object` and of `Thread`.
On CRuby 3.0.2, their `#inspect` shows they were first defined under `Thread` and then aliased in Object:
```
$ ruby -ve 'p [Mutex, Queue, SizedQueue, ConditionVariable]'
ruby 3.0.2p107 (2021-07-07 revision 0db68f0233) [x86_64-linux]
[Thread::Mutex, Thread::Queue, Thread::SizedQueue, Thread::ConditionVariable]
```
FWIW this contrasts to TruffleRuby which has:
```
$ ruby -ve 'p [Mutex, Queue, SizedQueue, ConditionVariable]'
truffleruby 22.0.0-dev-589c944e, like ruby 2.7.4, GraalVM CE Native [x86_64-linux]
[Mutex, Queue, SizedQueue, ConditionVariable]
```
(because these classes are all core now and I thought the Thread:: prefix was the alias since they moved to core)
However I believe most usages out there do *not* use the `Thread::` prefix, or in other words almost nobody uses the `Thread::` prefix for those classes.
And it seems very clearly confirmed by `gem-codesearch`:
```
$ gem-codesearch 'Thread::Mutex' | wc -l
254
$ gem-codesearch '\bMutex\b' | wc -l
19378
```
About 75x more common to use `Mutex` than `Thread::Mutex` it seems.
```
$ gem-codesearch 'Thread::Queue' | wc -l
138
$ gem-codesearch '\bQueue\b' | wc -l
38174
```
About 276x more common to use `Queue` than `Thread::Queue` it seems.
```
$ gem-codesearch 'Thread::ConditionVariable' | wc -l
110
$ gem-codesearch '\bConditionVariable\b' | wc -l
2145
```
About 19.5x more common to use `ConditionVariable` than `Thread::ConditionVariable` it seems.
```
$ gem-codesearch 'Thread::SizedQueue' | wc -l
27
$ gem-codesearch '\bSizedQueue\b' | wc -l
633
```
About 23x more common to use `SizedQueue` than `Thread::SizedQueue` it seems.
So I propose to update the canonical names of these classes to be without the `Thread::` prefix, to represent the vast majority of usages, and also the fact these classes are core now and not stdlib.
In other words, for 3.1.0 I propose:
```
$ ruby -ve 'p [Mutex, Queue, SizedQueue, ConditionVariable]'
ruby 3.1.0 ...
[Mutex, Queue, SizedQueue, ConditionVariable]
```