irb

# File lib/irb/ext/multi-irb.rb, line 189
  def IRB.irb(file = nil, *main)
    workspace = WorkSpace.new(*main)
    parent_thread = Thread.current
    Thread.start do
      begin
        irb = Irb.new(workspace, file)
      rescue
        print "Subirb can't start with context(self): ", workspace.main.inspect, "\n"
        print "return to main irb\n"
        Thread.pass
        Thread.main.wakeup
        Thread.exit
      end
      @CONF[:IRB_RC].call(irb.context) if @CONF[:IRB_RC]
      @JobManager.insert(irb)
      @JobManager.current_job = irb
      begin
        system_exit = false
        catch(:IRB_EXIT) do
          irb.eval_input
        end
      rescue SystemExit
        system_exit = true
        raise
        #fail
      ensure
        unless system_exit
          @JobManager.delete(irb)
          if @JobManager.current_job == irb
            if parent_thread.alive?
              @JobManager.current_job = @JobManager.irb(parent_thread)
              parent_thread.run
            else
              @JobManager.current_job = @JobManager.main_irb
              @JobManager.main_thread.run
            end
          end
        end
      end
    end
    Thread.stop
    @JobManager.current_job = @JobManager.irb(Thread.current)
  end