> I wonder if I could run an idea I've had by this list. It seems to
> me you could get some of the desired effects of lazy evaluation by using
> continuation passing style in code. For example, take this psuedo-code
> using CPS to represent an infinite data type.
This has been known for a lon
> > In a fit of madness, I have agreed to deliver a 50-minute lecture
> > on type classes to an audience of undergraduate students. These
> > students will have seen some simple typing rules for F2 and will
> > have some exposure to Hindley-Milner type inference in the context
> > of ML.
>
On Saturday, January 25, 2003, at 04:14 AM, Andrew J Bromage wrote:
G'day all.
On Fri, Jan 24, 2003 at 06:13:29PM -0500, Norman Ramsey wrote:
In a fit of madness, I have agreed to deliver a 50-minute lecture
on type classes to an audience of undergraduate students. These
students will have s
On Sun, 26 Jan 2003, Norman Ramsey wrote:
> > > In a fit of madness, I have agreed to deliver a 50-minute lecture
> > > on type classes to an audience of undergraduate students. These
> > > students will have seen some simple typing rules for F2 and will
> > > have some exposure to Hindley-Mi
On Sun, 26 Jan 2003 19:07:01 -0500 (EST)
Dean Herington <[EMAIL PROTECTED]> wrote:
> What may distinguish Haskell from typical OO languages (I'm not an
> expert on them) is that in Haskell such polymorphic functions could
> (always or at least nearly so) be specialized statically for their
> u
Can someone explain why the type declaration for `g` is required in the
following?
class RT r t where rt :: r -> t
data D t = Dt t | forall r. RT r t => Dr r
f :: D t -> D t
f = g
where -- g :: D t -> D t
g (Dr r) = Dt (rt r)
As given above, the program evokes these error messages:
w
Because you could have an instance:
instance RT r t1
and another instance for a t2 /= t1:
instance RT r t2
then when you say:
g (Dr r) = Dt (r t)
then, 'r t' could either have type t1 or t2, thus giving the result value
type 'Dt t1' or 'Dt t2'.
If your class had fundeps 'r -> t', then
