Create dynamically named class within module namespace

Question

I'm working with a Grape API and I have models which have a url attribute that I'm using to dynamically mount endpoints for. I need to be able to version them and I'm having trouble getting them to be properly namespaced when they're generated.

If I create a class within a module, that class is namespaced.

module MyModule
  module SubModule
    class MyClass
    end
  end
end
=> nil 
MyModule::SubModule::MyClass
=> MyModule::SubModule::MyClass

However, if I dynamically, create the class within a module, it isn't namespaced.

module MyModule
  module SubModule
    dynamic_name = "ClassName"
    Object.const_set(dynamic_name, Class.new)
  end
end
=> ClassName 
MyModule::SubModule::ClassName
NameError: uninitialized constant MyModule::SubModule::ClassName
ClassName
=> ClassName

Is there a way to namespace a dynamically created class?

Well, you *explicitly* tell Ruby to set the constant in `Object`, what did you expect? You can *explicitly* tell Ruby to set the constant somewhere else in *exactly the same way*. — Jörg W Mittag, Aug 20 '17 at 17:49
Thanks Max! Jorg, you're right, but in this case Max hit the nail on the head. I should've set it in the current scope. — Joshua Hunter, Aug 21 '17 at 20:54

score 3 · Accepted Answer · answered Aug 18 '17 at 23:03

3

Object.const_set explicitly sets the constant in the Object namespace, which is the root namespace. If you use const_set without Object, it will set the constant in whatever the current namespace is, which is MyModule::SubModule in your example.

answered Aug 18 '17 at 23:03

dtroof

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Create dynamically named class within module namespace

1 Answers1