raise_again.rb

class MyError < StandardError; end
 
def repeat_block(max_repeat, &block)
  challange = Proc.new do |cnt|
    begin
      block.call
      puts "success."
    rescue MyError => e
      if cnt > 0
        challange.call(cnt-1)
      else
        puts "failure."
        raise e
      end
    end
  end
 
  challange.call(max_repeat)
end
 
repeat_block(3) do
  puts "start."
  raise MyError unless rand(3) == 0
  puts "end."
end