On Dec 30, 2011, at 10:34 AM, Artyom Kazak wrote: > Gregg Reynolds <d...@mobileink.com> писал(а) в своём письме Fri, 30 Dec 2011 > 17:23:20 +0200: > >> Regarding side-effects, they can be (informally) defined pretty simply: any >> non-computational effect caused by a computation is a side-effect. > > I wonder: can writing to memory be called a “computational effect”? If yes, > then every computation is impure. If no, then what’s the difference between > memory and hard drive? >
Great question! It suggests that the line between computation and its side effects is not as clear-cut as we (well, I) thought. If computations are Platonistic, mathematico-logical "things", then is actual computation a side-effect of the Platonic Idea? Heh heh. > By the way, the Data.HashTable is in IO monad. Is it impure? Would it be pure > if designers had chosen to use ST instead? Dunno, somebody else will have to answer that one. -Gregg _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
