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Ruby Ruby Modules Store Inventory Using Modules Extend and Include

Posted by Joseph Park
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Joseph Park
Front End Web Development Techdegree Student 6,746 Points

Why have the ClassMethod?

So he has the method self.include(klass) in the Inventoryable module which just extends the methods in the ClassMethod module into the Inventoryable module. So why have the ClassMethod module if the extend just makes the methods in that module available in the Inventoryable module. Can you not just put the methods all in one module (inventoryable module)

1 Answer

Shoko Ishigaki
Shoko Ishigaki
21,826 Points
Shoko Ishigaki
Shoko Ishigaki
21,826 Points

We want other class to "extend" the ClassMethods so that all methods defined there will mix in to the class methods not instances of the class. If we put all the methods in one module and class includes it, all the methods will mix in to instances of the class which is not what we want here.

Hope this will help.