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

| 

        # Array.|

(from ruby core)
---
    array | other_array -> new_array

---

Returns the union of `array` and Array `other_array`; duplicates are
removed; order is preserved; items are compared using `eql?`:
    [0, 1] | [2, 3] # => [0, 1, 2, 3]
    [0, 1, 1] | [2, 2, 3] # => [0, 1, 2, 3]
    [0, 1, 2] | [3, 2, 1, 0] # => [0, 1, 2, 3]

Related: Array#union.

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.