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

group 

        # PrettyPrint.group

(from ruby core)
---
    group(indent=0, open_obj='', close_obj='', open_width=open_obj.length, close_width=close_obj.length) { || ... }

---

Groups line break hints added in the block. The line break hints are all
to be used or not.

If `indent` is specified, the method call is regarded as nested by
nest(indent) { ... }.

If `open_obj` is specified, `text open_obj, open_width` is called before
grouping. If `close_obj` is specified, `text close_obj, close_width` is
called after grouping.

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.