At some point in the past, someone wrote: >> Actually, I've been wondering about this. If my understanding is >> correct, Haskell lists are basicly singly-linked lists of cons cells (is >> that correct?) A simple (I think) thing to do would be to make the >> lists doubly-linked and circular. That would let us do nice things like >> have O(1) primops for reverse, tail, (++) and other things that access >> lists at the end. However, I'm still pretty new to FP in general, so I >> don't know if there are any theoretical reasons why something like this >> couldn't work.
On Fri, Oct 08, 2004 at 02:42:28PM +0100, Keith Wansbrough wrote: > x = [3,5,7] > primes = 2:x > odds = 1:x > You can't do sharing like this if your lists are doubly-linked; lots > of cool algorithms depend on this sharing. That constraint makes various other things painful. I suppose there is no one-size-fits-all solution. -- wli _______________________________________________ Haskell-Cafe mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/haskell-cafe
