On Wed, Sep 29, 2004 at 02:43:45PM +0100, Simon Peyton-Jones wrote:
| I meant that the implementation like | | minimum [x] = x | minimum (x:y:xs) = if x > y then minimum (y:xs) | else minimum (x:xs)
It would be great if this was the defn of minimum in the Report. But it isn't.
Consider
data T = T1 | T2 instance Ord T where min x T2 = T2 min x y = error "urk"
Now try minimum [T1,T2,T2] your defn gives "urk", but the Report gives T2.
Stupid, I know, but that's what it says.
So the best thing seems to be to give monomorphic instances of minimum for types where we know the instances!
Simon
I thought naively that the Report function definitions can be treated more flexy, varied by implementations, with preserving some declared main properties. But, probably, less freedom is allowed: treating of Bottom to be preserved and such. All right. ----------------- Serge Mechveliani mechvel@botik.ru