Issue #19079 has been updated by matz (Yukihiro Matsumoto). Status changed from Open to Rejected The `DelegateClass` defines an anonymous class and defines forwarding methods to the class. The reported (so-called) issue is a natural consequence of the above behavior. `include` add methods defined in a module **above** the current class, so forwarding methods have higher precedence. If you (re)define a method, it overwrites the forwarding method. My opinion is that your assumption is wrong, so we don't need to fix. If you think we need to implement your assumption, you need to persuade us with the real world use-case. Matz. ---------------------------------------- Bug #19079: Modules included in a DelegateClass cannot override delegate methods https://bugs.ruby-lang.org/issues/19079#change-100371 * Author: jonathanhefner (Jonathan Hefner) * Status: Rejected * Priority: Normal * ruby -v: ruby 3.1.2p20 * Backport: 2.7: UNKNOWN, 3.0: UNKNOWN, 3.1: UNKNOWN ---------------------------------------- Because `DelegateClass` defines delegate methods on the class itself, those delegate methods come first in the method lookup chain. This prevents included modules from overriding delegate methods: ```ruby Base = Class.new do def foo "base" end end Helper = Module.new do def foo "helper" end end WithHelper = DelegateClass(Base) { include Helper } WithHelper.new(Base.new).foo # => "base" ``` One possible solution would be to define the delegate methods in a separate module. That way, other modules could come before it in the method lookup chain. -- https://bugs.ruby-lang.org/