This is a Ruby tree! It shows every object from the Ruby Programming Language in a tree format.

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        # OpenStruct.[]

(from ruby core)
---
    ostruct[name]  -> object

---

Returns the value of an attribute, or `nil` if there is no such
attribute.

    require "ostruct"
    person = OpenStruct.new("name" => "John Smith", "age" => 70)
    person[:age]   # => 70, same as person.age

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.