On 2006-07-27 at 01:33EDT Paul Hudak wrote: > Thanks for asking about this -- it probably should be in the paper. Dan > Doel's answer is closest to the truth: > > I imagine the answer is that having the syntax for it looks nicer/is > clearer. "if a b c" could be more cryptic than "if a then b else c" > for some values of a, b and c. > > except that there was also the simple desire to conform to convention > here (I don't recall fewer parentheses being a reason for the choice).
In a sense, it explicitly wasn't: I suggested "if _ then _ else _ fi" -- something I was long used to from Algol68 -- but it was rejected on the ground that there wasn't a dangling else problem in Haskell. I probably muttered something about wanting things to be self-bracketing (I've certainly grumbled inwardly since about having to write "(if _ then _ else _)¹" in some Haskell contexts), but since I'm quite slow witted, I expect that the discussion had moved on by then. > In considering the alternative, I remember the function "cond" being > proposed instead of "if", in deference to Scheme and to avoid confusion > with people's expectations regarding "if". Did we talk about Dijkstra's "fat bar", or was that a discussion I had elsewhere? Jón [1] which I find ugly, and besides, making all like constructs self-bracketing would have allowed a saner (to my mind) layout rule. -- Jón Fairbairn Jon.Fairbairn at cl.cam.ac.uk _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
