Did you actually test the code? mod1.constants == mod2.constants returns true.
$ cat main.rb
ns = Namespace.new
mod1 = Object
mod2 = ns::Object
p mod1 #=> Object
p mod2 #=> Object
p mod1.object_id == mod2.object_id #=> true
p mod1.constants == mod2.constants #=> true
$ 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.
Object
Object
true
true
It's great that you're splitting the ticket and discussing each topic in detail. Thank you for that.
That said, when creating tickets, please make sure to include the test code, what you expected to happen, and what actually happened, in the usual format.
Full reproducer, showing that even though Object is the same reference in all namespaces it can have different constants in different namespaces, but only if calling constants in that namespace:
$ RUBY_NAMESPACE=1 ruby -ve 'ns = Namespace.new; File.write "ns.rb", "O = Object; OC = Object.constants"; ns.require "./ns"; p Object.equal?(ns::O); p Object.constants == ns::OC; p Object.constants == ns::Object.constants'
ruby 3.5.0dev (2025-05-10T07:50:29Z namespace-on-read-.. bd4f57f96b) +PRISM [x86_64-linux]
ruby: warning: Namespace is experimental, and the behavior may change in the future!
See doc/namespace.md for know issues, etc.
true
false
true
I think this is expected behavior for Namespace so not sure it's worth reopening.
It does mean that with Namespace even though two objects (specifically core classes and modules) might be equal they are actually different when looked at in different namespaces.
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