1 Mar
2006
1 Mar
'06
11:26 p.m.
On Thu, Mar 02, 2006 at 03:53:45AM -0000, Claus Reinke wrote:
- Mul recurses down a type in its second parameter - types in Haskell are finite - there is a non-terminating Mul inference
the problem is that we have somehow conjured up an infinite type for Mul to recurse on without end! Normally, such infinite types are ruled out by occurs-checks (unless you are working with Prolog III;-), so someone forgot to do that here. why? where? how?
Polymorphic recursion allows the construction of infinite types if I understand what you mean. if you are clever (or unlucky) you can get jhcs middle end to go into an infinite loop by using them.
-- an infinite binary tree data Bin a = Bin a (Bin (a,a))
John -- John Meacham - ⑆repetae.net⑆john⑈