From: "fxn (Xavier Noria)" Date: 2022-01-24T13:38:16+00:00 Subject: [ruby-core:107260] [Ruby master Feature#18273] Class#subclasses Issue #18273 has been updated by fxn (Xavier Noria). @zverok one thing is "subclasses can vanish", because the language is dynamic (like ancestors can change), and a different thing is that in this program: ```ruby Class.new Object.subclasses ``` you cannot tell me what is the 2 line going to return. Personally, I find this non-deterministic behavior unacceptable for an API of this level. ---------------------------------------- Feature #18273: Class#subclasses https://bugs.ruby-lang.org/issues/18273#change-96121 * 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 -- https://bugs.ruby-lang.org/ Unsubscribe: