module Enumerable
  def [](*args)
    arr = self.to_a
    r = []    
    args.each{ |arg|
      case arg
      when Proc
        r.concat arr.find_all &arg
      when Range
        r.concat arr[arg]
      when Numeric
        r << arr[arg]
      else
        raise ArgumentError, "Invalid enumeration"
        #super if defined? super
      end
    }
    r
  end
end


# --- test ---

if $0 == __FILE__

  p ("a".."z")[2,5,3..4]
  
end