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

nan? 

        # Float.nan?

(from ruby core)
---
    nan? -> true or false

---

Returns `true` if `self` is a NaN, `false` otherwise.

    f = -1.0     #=> -1.0
    f.nan?       #=> false
    f = 0.0/0.0  #=> NaN
    f.nan?       #=> true

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.