On Mon, 2009-11-30 at 23:30 +0000, Ian Lynagh wrote: > On Mon, Nov 30, 2009 at 11:05:21PM +0000, Duncan Coutts wrote: > > On Mon, 2009-11-30 at 17:26 +0000, Ian Lynagh wrote: > > > > > f2 x = x + case () of > > > () -> x > > > where x = 5 > > > > 10, same reason. > > So if you look at f2 from the perspective of someone new to the > language, given they understand the scoping of f1 and f3, would they > expect that where binding to scope over the entire RHS rather than just > the case expression? Maybe it's just me, but I don't think that would > match my intuition.
They would know that it has to be one or the other. The new person would reason that the language designers either picked > or >= for column offset. Which one they picked is something a new person would have to look up, or just try, or avoid. >From a casual perspective there's nothing subtle about this case, it does just look like a question of an arbitrary choice between >= vs >. Programmers don't (and do not have to) realise that in reality parsing this relies on the error rule. Duncan _______________________________________________ Cvs-ghc mailing list [email protected] http://www.haskell.org/mailman/listinfo/cvs-ghc
