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

^ 

        # Set.^

(from ruby core)
---
    ^(enum)

---

Returns a new set containing elements exclusive between the set
and the given enumerable object. `(set ^ enum)` is equivalent to
`((set | enum) - (set & enum))`.
    Set[1, 2] ^ Set[2, 3]                   #=> #<Set: {3, 1}>
    Set[1, 'b', 'c'] ^ ['b', 'd']           #=> #<Set: {"d", 1, "c"}>

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.