[ruby-core:113992] [Ruby master Feature#19742] Introduce `Module#anonymous?`

Issue #19742 has been updated by ioquatix (Samuel Williams). Should setting a temporary name make a module not anonymous? I found the following use cases in Rails: ```ruby unless controller_class.anonymous? controller_class.name.delete_suffix("Controller").underscore end ``` ```ruby def self.kind @kind ||= name.split("::").last.underscore.chomp("_validator").to_sym unless anonymous? end ``` ```ruby def self.controller_name @controller_name ||= (name.demodulize.delete_suffix("Controller").underscore unless anonymous?) end ``` ```ruby def controller_path @controller_path ||= name.delete_suffix("Controller").underscore unless anonymous? end ``` ```ruby def mailer_name @mailer_name ||= anonymous? ? "anonymous" : name.underscore end ``` So, I think the usage of anonymous is already ossified by Rails, even if I disagree. To me, anonymous means it cannot be named, but there is a difference between "proper noun" and "common noun". If you refer to a "person", the person does not have a proper name, they are anonymous. If you refer to "Samuel", you are referring to a specific person, which is not anonymous. ---------------------------------------- Feature #19742: Introduce `Module#anonymous?` https://bugs.ruby-lang.org/issues/19742#change-103650 * Author: ioquatix (Samuel Williams) * Status: Open * Priority: Normal ---------------------------------------- As a follow-on <from https://bugs.ruby-lang.org/issues/19521>gt;, I'd like propose we introduce `Module#anonymous?`. In some situations, like logging/formatting, serialisation/deserialization, debugging or meta-programming, we might like to know if a class is a proper constant or not. However, this brings about some other issues which might need to be discussed. After assigning a constant, then removing it, the internal state of Ruby still believes that the class name is permanent, even thought it's no longer true. e.g. ``` m = Module.new m.anonymous? # true M = m m.anonyomous # false Object.send(:remove_const, :M) M # uninitialized constant M (NameError) m.anonymous? # false ``` Because RCLASS data structure is not updated after the constant is removed, internally the state still has a "permanent class name". I want to use this proposal to discuss this issue and whether there is anything we should do about such behaviour (or even if it's desirable). Proposed PR: https://github.com/ruby/ruby/pull/7966 cc @fxn -- https://bugs.ruby-lang.org/