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How do I raise a fatal exception ruby?

Ruby has a fatal exception, but there is no guidance on how to raise it and I cannot figure it out. How do I raise a fatal exception in Ruby?

Solution

  • Sure you can.

    Try this

    FatalError = ObjectSpace.each_object(Class).find { |klass| klass < Exception && klass.inspect == 'fatal' }

    And then

    raise FatalError.new("famous last words")

    How does this work?

    • fatal is an internal class without associated top-level constant
    • ObjectSpace.each_object(Class) enumerates over all classes
    • find { ... } finds an exception class named "fatal"

    NB though, despite its name fatal is not special, it can be rescued. If you are looking for a way to end your program maybe best call the global exit method?

    begin
  raise FatalError.new
rescue Exception => e
  puts "Not so fatal after all..."
end