From: alxtskrnk@... Date: 2015-12-07T16:09:56+00:00 Subject: [ruby-core:71912] [Ruby trunk - Bug #11779] Module#using does not make sense as a method Issue #11779 has been updated by bug hit. Yukihiro Matsumoto wrote: > Can elaborate what do you want if `using` should not be a method. > Considering a new keyword would break existing code, I don't think it's a good idea. > I don't know what possibilities there are, it just struck me that it was not behaving at all as a method, methods affect their dynamically scoped receiver, `using` affects the lexically scoped currently open module. So a keyword, if it were possible, would be more appropriate. Don't know what else it could be. If it stays a method, what about #3 ```ruby module Bar def self.refined? ''.refined? rescue false end Foo.module_eval do using Refinement end end ``` what should happen here? ---------------------------------------- Bug #11779: Module#using does not make sense as a method https://bugs.ruby-lang.org/issues/11779#change-55318 * Author: bug hit * Status: Feedback * Priority: Normal * Assignee: * ruby -v: 2.2.3 * Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN ---------------------------------------- 1. it can't be called from another method 2. the receiver must be self 3. since refinements are lexically scoped the self receiver must match the currently open class #3 is particularly curious ```ruby module Refinement refine String do def refined? true end end end module Foo def self.refined? ''.refined? rescue false end end module Bar def self.refined? ''.refined? rescue false end Foo.module_eval do using Refinement end end p Foo.refined? #false ``` The module_eval `#using` call does not raise (it's not from a method and the receiver is self), but evidently because currently open class does not match self, it does not do anything. So it should at least raise. So `#using`, though a method, does not function as a method, which is misleading. -- https://bugs.ruby-lang.org/