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

matched_size 

        # StringScanner.matched_size

(from ruby core)
---
    matched_size()

---

Returns the size of the most recent match in bytes, or `nil` if there
was no recent match.  This is different than `matched.size`, which will
return the size in characters.

    s = StringScanner.new('test string')
    s.check /\w+/           # -> "test"
    s.matched_size          # -> 4
    s.check /\d+/           # -> nil
    s.matched_size          # -> nil

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.