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

- 

        # Integer.-

(from ruby core)
---
    self - numeric -> numeric_result

---

Performs subtraction:

    4 - 2              # => 2
    -4 - 2             # => -6
    -4 - -2            # => -2
    4 - 2.0            # => 2.0
    4 - Rational(2, 1) # => (2/1)
    4 - Complex(2, 0)  # => (2+0i)

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.