Can someone explain why the following doesn't work? Is there some other
way to achieve the same effect (declaring a set of instances for pair-like
types in one go)?
Thanks.
Dean
swan(108)% cat Test1.hs
{-# OPTIONS -fglasgow-exts #-}
class R r where
rId :: r -> String
class (R r) => RT r t
> Maybe I have a OT question .All is running fine with Hugs98 but I have
> headache to work with Greencard . It will not run (binary and also source
> .rpm fails )on SUSE 8.2 Pro
Can you give me a bit more information about what is going wrong?
Does the install fail?
Does the install succeed b
On Mon, Sep 29, 2003 at 07:31:33AM -0700, Levent Erkok wrote:
> > > BTW, in GHC 6.2 with the -fglasgow-exts -farrows flags, you will be able
> > > to use either mdo or do...rec for monads and for arrows, as an experiment.
> > > (Maybe "rec" wasn't such a great keyword to take from the identifier
>
> Another approach to value recursion was recently given by Sabry and Moggi
> in their latest FICS paper: They have an mfix-like operator for
> continuations there, but it doesn't satisfy left-shrinking either.
The paper in question is available at:
http://www.cs.indiana.edu/~sabry/papers/val
On Wed, 17 Sep 2003, Brandon Michael Moore wrote:
> > > Don't the laws for loop and mfix justify the transformation?
> >
> > The loop axioms do, but Levent didn't assume right tightening, which
> > corresponds to moving bindings down from a rec, because monads like
> > exceptions don't satisfy it
On Wed, 17 Sep 2003, Brandon Michael Moore wrote:
> The problem with that is that not all monads support recursive bindings.
> We can deal with that, but the desuagring of a do statement wouldn't be so
> trivial any more. The most sensible approach I can think of is to analyze
> the bindings an
> On the necessity of rec syntax, how is a statement like
> do rec binds1
> rec binds2
> stmts
> different from
> do BV1 <- mdo binds1
>return BV1
> BV2 <- mdo binds2
>return BV2
> stmts
> where BVn is a tuple of all the variables bound in bindsn.
--- "Gottfried F. Zojer" <[EMAIL PROTECTED]> wrote:
> P.s. Is somebody using Haskell in combination with
> PostgreSQL via C/or C++ interface.
The PostgreSQL interface is available with HSQL
library. The HSQL is available from:
https://sourceforge.net/project/showfiles.php?group_id=65248
Cheers
Hello to all,
I m new to Haskell but not to functional programming .
Maybe I have a OT question .All is running fine with Hugs98 but I have headache to
work with Greencard . It will not run (binary and also source .rpm fails )on SUSE 8.2
Pro
Any hint is welcomed .
Gottried F. Zojer
P.s.
