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class_variables 

        # Module.class_variables

(from ruby core)
---
    mod.class_variables(inherit=true)    -> array

---

Returns an array of the names of class variables in *mod*. This includes
the names of class variables in any included modules, unless the
*inherit* parameter is set to `false`.

    class One
      @@var1 = 1
    end
    class Two < One
      @@var2 = 2
    end
    One.class_variables          #=> [:@@var1]
    Two.class_variables          #=> [:@@var2, :@@var1]
    Two.class_variables(false)   #=> [:@@var2]

This is MURDOC! A Ruby documentation browser inspired by Smalltalk-80. It allows you to learn about Ruby by browsing through its class hierarchies, and see any of its methods.