[#106939] [Ruby master Bug#18455] `IO#close` has poor performance and difficult to understand semantics. — "ioquatix (Samuel Williams)" <noreply@...>

Issue #18455 has been reported by ioquatix (Samuel Williams).

10 messages 2022/01/01

[#106977] [Ruby master Feature#18461] closures are capturing unused variables — "bughit (bug hit)" <noreply@...>

Issue #18461 has been reported by bughit (bug hit).

12 messages 2022/01/05

[#106994] [Ruby master Feature#18462] Proposal to merge WASI based WebAssembly support — "katei (Yuta Saito)" <noreply@...>

Issue #18462 has been reported by katei (Yuta Saito).

8 messages 2022/01/07

[#106996] [Ruby master Feature#18463] Random number generation with xoshiro — "bbrklm (Benson Muite)" <noreply@...>

Issue #18463 has been reported by bbrklm (Benson Muite).

8 messages 2022/01/07

[#107005] [Ruby master Bug#18464] RUBY_INTERNAL_EVENT_NEWOBJ tracepoint causes an interpreter crash when combined with Ractors — "kjtsanaktsidis (KJ Tsanaktsidis)" <noreply@...>

Issue #18464 has been reported by kjtsanaktsidis (KJ Tsanaktsidis).

14 messages 2022/01/08

[#107008] [Ruby master Bug#18465] Make `IO#write` atomic. — "ioquatix (Samuel Williams)" <noreply@...>

Issue #18465 has been reported by ioquatix (Samuel Williams).

16 messages 2022/01/09

[#107073] [Ruby master Feature#18481] Porting YJIT to Rust (request for feedback) — "maximecb (Maxime Chevalier-Boisvert)" <noreply@...>

Issue #18481 has been reported by maximecb (Maxime Chevalier-Boisvert).

26 messages 2022/01/12

[#107106] [Ruby master Bug#18487] Kernel#binding behaves differently depending on implementation language of items on the stack — "alanwu (Alan Wu)" <noreply@...>

Issue #18487 has been reported by alanwu (Alan Wu).

11 messages 2022/01/13

[#107190] [Ruby master Feature#18498] Introduce a public WeakKeysMap that compares by equality — "byroot (Jean Boussier)" <noreply@...>

Issue #18498 has been reported by byroot (Jean Boussier).

17 messages 2022/01/19

[#107203] [Ruby master Bug#18501] [BUG] try to mark T_NONE object in RubyVM::InstructionSequence. load_from_binary — "byroot (Jean Boussier)" <noreply@...>

Issue #18501 has been reported by byroot (Jean Boussier).

8 messages 2022/01/20

[#107204] [Ruby master Bug#18502] Make ruby-2.7.5 on Solaris 10 ld.so.1: gcc: fatal: libintl.so.8: open failed: No such file or directory — "dklein (Dmitri Klein)" <noreply@...>

Issue #18502 has been reported by dklein (Dmitri Klein).

8 messages 2022/01/20

[#107275] [Ruby master Bug#18512] MacOS 12.1 Monterey Bug — "oucl5976@... (Paul Liu)" <noreply@...>

Issue #18512 has been reported by [email protected] (Paul Liu).

9 messages 2022/01/25

[#107291] [Ruby master Bug#18518] NoMemoryError + [FATAL] failed to allocate memory for twice 1 << large — "Eregon (Benoit Daloze)" <noreply@...>

Issue #18518 has been reported by Eregon (Benoit Daloze).

12 messages 2022/01/26

[#107310] [Ruby master Bug#18555] Running "bundle exec middleman server" on M1 Mac gives [BUG] Bus Error at 0x0000000104b04000 — "anthonyaykut (Anthony Aykut)" <noreply@...>

Issue #18555 has been reported by anthonyaykut (Anthony Aykut).

13 messages 2022/01/28

[#107346] [Ruby master Misc#18557] DevMeeting-2022-02-17 — "mame (Yusuke Endoh)" <noreply@...>

Issue #18557 has been reported by mame (Yusuke Endoh).

18 messages 2022/01/29

[#107392] [Ruby master Bug#18560] "Compaction isn't available on this platform" error running PG test suite on ppc64le — "vo.x (Vit Ondruch)" <noreply@...>

Issue #18560 has been reported by vo.x (Vit Ondruch).

7 messages 2022/01/31

[ruby-core:107257] [Ruby master Feature#18273] Class#subclasses

From: "fxn (Xavier Noria)" <noreply@...>
Date: 2022-01-24 11:19:23 UTC
List: ruby-core #107257
Issue #18273 has been updated by fxn (Xavier Noria).


@zverok Absolutely, the API of a dynamic language should be dynamic.

For example, take this:

```ruby
C = Class.new
Object.subclasses # (1)

D = Class.new
Object.subclasses # (2)
```

For the user, it makes sense that (1) includes `C`, and (2) includes `C` and `D`. They are guaranteed to be there, because `Object` has a strong reference to them via its constants table, and this fact belongs to the public API of Ruby. (My points are not about constants, but in that example, in order to say that (2) has `C` and `D` I need to say there's a strong reference somewhere.)

If you later on add a mixin:

```ruby
C.include(M)
```

of course, `C.ancestors` is supposed to reflect that change.

What would be strange is that

```ruby
C.ancestors
C.ancestors
```

could yield different results if you did not change the ancestor chain in between.

That is, you didn't do anything to change that collection.

> but is this difference practicalor only affects "theoretical clarity"

It's not marble tower theoretical clarity, it is just that the API of the language has to agree with the language model.

There are APIs that conceptually are about live objects, like `ObjectSpace`. But `Class#subclasses` is not at that level, conceptually. `Class#subclasses` is at the level of `Module#ancestors`, in my view.

> I assume that as a developer of the Zeitwerk you maybe can provide some insight on practical consequences?

In my view, the API introduces a broken window, a method that behaves in a non-deterministic way. Broken windows leak.



----------------------------------------
Feature #18273: Class#subclasses
https://bugs.ruby-lang.org/issues/18273#change-96118

* Author: byroot (Jean Boussier)
* Status: Closed
* Priority: Normal
----------------------------------------
Ref: https://github.com/rails/rails/pull/43481

Something we forgot to mention in [Feature #14394], is either a parameter or another method to only get direct descendants.

Active Support has been offering `Class.subclasses` as:

```ruby
  def subclasses
    descendants.select { |descendant| descendant.superclass == self }
  end
```

It seems a bit silly to grab all descendants and then restrict the list when `Class#descendants` had to do some recursion to get them all in the first place.

### Proposal

We could either implement `Class#subclasses` directly, or accept a parameter in `Class#descendants`, e.g. `descendants(immediate = false)`.

cc @eregon



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