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included_modules 

        # Module.included_modules

(from ruby core)
---
    mod.included_modules -> array

---

Returns the list of modules included or prepended in *mod* or one of
*mod*'s ancestors.

    module Sub
    end

    module Mixin
      prepend Sub
    end

    module Outer
      include Mixin
    end

    Mixin.included_modules   #=> [Sub]
    Outer.included_modules   #=> [Sub, Mixin]

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.