This is a Ruby tree! It shows every object from the Ruby Programming Language in a tree format.
# Math::DomainError < StandardError (from ruby core) --- Raised when a mathematical function is evaluated outside of its domain of definition. For example, since `cos` returns values in the range -1..1, its inverse function `acos` is only defined on that interval: Math.acos(42) *produces:* Math::DomainError: Numerical argument is out of domain - "acos" ---
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.