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

delete_if 

        # Hash.delete_if

(from ruby core)
---
    hash.delete_if {|key, value| ... } -> self
    hash.delete_if -> new_enumerator

---

If a block given, calls the block with each key-value pair; deletes each
entry for which the block returns a truthy value; returns `self`:
    h = {foo: 0, bar: 1, baz: 2}
    h.delete_if {|key, value| value > 0 } # => {:foo=>0}

If no block given, returns a new Enumerator:
    h = {foo: 0, bar: 1, baz: 2}
    e = h.delete_if # => #<Enumerator: {:foo=>0, :bar=>1, :baz=>2}:delete_if>
    e.each { |key, value| value > 0 } # => {:foo=>0}

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.