Issue #21319 has been updated by mame (Yusuke Endoh). I cannot repro the issue. ```ruby # main.rb ns = Namespace.new ns.require "./sub" p :success ``` ```ruby # sub.rb module M end class C include M end ``` ``` $ RUBY_NAMESPACE=1 ./miniruby main.rb ./miniruby: warning: Namespace is experimental, and the behavior may change in the future! See doc/namespace.md for know issues, etc. :success ``` Can you clarify how to reproduce the issue? ---------------------------------------- Bug #21319: Namespaces do not support including mixins https://bugs.ruby-lang.org/issues/21319#change-113074 * Author: fxn (Xavier Noria) * Status: Open * Backport: 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN ---------------------------------------- The following program ```ruby module M end class C include M end ``` fails under a namespace with error ``` 'Module#include': Cannot include refinement (TypeError) ``` -- https://bugs.ruby-lang.org/