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FiberError 

        # FiberError < StandardError

(from ruby core)
---
Raised when an invalid operation is attempted on a Fiber, in particular
when attempting to call/resume a dead fiber, attempting to yield from
the root fiber, or calling a fiber across threads.

    fiber = Fiber.new{}
    fiber.resume #=> nil
    fiber.resume #=> FiberError: dead fiber called
---

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.