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RuntimeError

        # RuntimeError < StandardError

(from ruby core)
---
A generic error class raised when an invalid operation is attempted.
Kernel#raise will raise a RuntimeError if no Exception class is
specified.

    raise "ouch"

*raises the exception:*

    RuntimeError: ouch
---

      

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.