Am Montag, 24. Januar 2005 22:59 schrieb Benjamin Franksen: > Both are wrong. 'just the result matters' is the correct POV for functions, > but not for IO actions. 'everything matters' is wrong even for IO actions, > because the actual value returned when the action is executed is completely > irrelevant to the IO action's identity.
Now that I cannot swallow, that would mean return 4 == return 5. I suppose you didn't mean that, though. Maybe, the internal workings are irrelevant, only visible side-effects and the returned value? But which side-effects are relevant? > And also some of the electrons on transistor 19348587434 on the CPU chip > move with a slightly reduced velocity due to the computer user shouting > curses at his machine... could that alter the number of reductions? > > Seriously, the model in which the 'sameness' resp. identity of IO actions > is defined takes into account only (a subset of all) externally observable > effects, not the way a certain interpreter/compiler executes the action > internally. > > I'll stop here; think I have made my point Yes, and I still don't know which effects do count and why these and not others. > > Ben > _______________________________________________ > Haskell-Cafe mailing list > Haskell-Cafe@haskell.org > http://www.haskell.org/mailman/listinfo/haskell-cafe _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe