gistfile1.rb

  def self.log(method, options = {})
    the_logger = options[:logger] || send(:logger)
    meth = the_logger.respond_to?(:debug) ? :debug : :puts
    
    define_method("#{method}_with_logging") do |*args|
      the_logger.send(meth, "Before method: #{method} arguments: #{args.inspect}")
      result = send("#{method}_without_logging", *args)
      the_logger.send(meth, "After method: #{method} result: #{result.inspect}")
      result
    end
    alias_method_chain method, "logging"
  end
  
  log :build_groups_for_select, :logger => logger