David Menendez wrote:
> If desired, we could easily define a class for commutative monads, and
> then state that ListT m is only a monad if m is a commutative monad.
If we do that, can I suggest that we use some name other
than ListT for that? So far, we seem to agree that most
practical applicati
On 10/14/07, Dan Piponi <[EMAIL PROTECTED]> wrote:
> On 10/14/07, Yitzchak Gale <[EMAIL PROTECTED]> wrote:
> > Not very much, I suspect. That "monad" really is broken -
> > it's not a monad at all.
>
> Depending on your point of view, ListT isn't broken. It correctly
> transforms commutative monads
On 10/14/07, Yitzchak Gale <[EMAIL PROTECTED]> wrote:
> Interesting. What do you mean by a "commutative monad"?
> It can't be a monad with some sort of additional commutative
> law, because the old ListT doesn't even satisfy the monad
> laws. Or does it in some sense?
If m is a commutative monad,
On 10/14/07, Yitzchak Gale <[EMAIL PROTECTED]> wrote:
> Not very much, I suspect. That "monad" really is broken -
> it's not a monad at all.
Depending on your point of view, ListT isn't broken. It correctly
transforms commutative monads into monads. The problem is that you
can't express "commutati
Hi Ian, thanks for responding to my plea!
I am renaming this thread and moving it to libraries.
Please respond there.
I wrote:
>> http://haskell.org/haskellwiki/ListT_done_right
>> and not the broken implementation that comes with mtl.
>> (Finally fixed in 6.8? Please?)
Ian Lynagh wrote:
> If yo
