gistfile1.rb

# Execute a block +number+ times. Block should be a predicate (return true/false)
#
# Use procs/lambdas to define callbacks:
#   :success => ...
#   :retry   => ...
#   :failure => ...
def do_over(number, options = {}, &block)
  options = {
    :success  => lambda { puts "SUCCESS" },
    :retry    => lambda { puts "RETRY" },
    :failure  => lambda { puts "FAILURE"; raise "Giving up!" }
  }.merge(options)

  number.times do |n|
    if yield
      options[:success].call(n)
      break
    else
      if n == (number - 1)
        options[:failure].call(n)
      else
        options[:retry].call(n)
      end
    end
  end
end