>> I can't get this to work.

Hmm.

>> E:\Ruby>ruby try.rb
>> 4 4
>> try.rb:2:in `%': too few arguments. (ArgumentError)
>>         from try.rb:2
>>         from try.rb:2:in `map'
>>         from try.rb:2
> 
> irb(main):006:0> s=1; x=5; [*s...s+x]
> => [1, 2, 3, 4, 5]
> irb(main):007:0> s=1; x=5; [*s...s+=x]
> => []
> irb(main):009:0> s=1; x=5; s...s+=x
> => 6...6

Interesting:

C:\development>ruby -v -e "s=1; x=5; p s...s+=x"
ruby 1.8.5 (2006-08-25) [i386-mswin32]
1...6


cheers

Simon