Threads - attempt to call method split a nil value

[mattdns1006]

I am running some threads but I can't get the string split method to work, the method doesn't exist in the threads but it does work normally.
The below code prints "string" for each thread however if I add the line which is currently commented out it throws the error;

donkeys.lua:16: attempt to call method 'split' (a nil value)

donkeys = Threads(
                      params.nThreads,
                         function(idx)
                                 require "torch"
                                 require "string"
                                 tid = idx -- Thread id
                                 print(string.format("Initialized thread with id : %d.", did))
                                 eg = "x,y,z"
                                 print(type(eg)) 
                                 --print(eg:split(",")) 
                         end
                         )
end                     

[deltheil]

It is provided by xlua.

[mattdns1006]

perfect thanks a lot