> Hello, I am interested in using global variables (in GHC). I need a > variable to store list of Integers to store temporary results. I > have been reading the module MVar, but I wonder if there is an > alternative way of doing it. I have already implemented my function > using an auxiliar argument where I put my lists of Integers. Will > the use of a global variable improve my function?
no!-) ah, well, perhaps.. As you've already got your function, using auxiliary arguments, you probably don't really need to re-write it in a less functional style. But you will have noticed that much of your code repeatedly does the same thing - passing the auxiliary around. It's good functional programming practice to abstract away repeated code (both for reuse and to get more concise code). One way to do that will lead you into monads (your function is a state transformer, transforming the state of the auxiliary list at each step), still a functional solution. If you really, and absolutely want and must use global, mutable variables in a functional language, you might find a recent paper by John Hughes helpful, on that very topic. See his home page: http://www.cs.chalmers.se/~rjmh/ Hth, Claus _______________________________________________ Haskell mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/haskell