Issue #19742 has been updated by fxn (Xavier Noria). @Dan0042 right, it could be the case that in Rails anything autoloadable has a permanent name and that has made the predicate sufficient in practice after 3.0. I introduced that predicate myself back in 2010 because you got an empty string in 1.8 and `nil` in 1.9, so `anonymous?` at the same time had meaning and was portable. ---------------------------------------- Feature #19742: Introduce `Module#anonymous?` https://bugs.ruby-lang.org/issues/19742#change-106271 * Author: ioquatix (Samuel Williams) * Status: Open * Priority: Normal ---------------------------------------- As a follow-on <from https://bugs.ruby-lang.org/issues/19521>, 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/