G'day.
Quoting Janis Voigtlaender [EMAIL PROTECTED]:
Hmm, but I can easily define an instance of Eq that does not satisfy
this invariant. And I want the generated free theorem to be true for any
legal Haskell program.
I would think that if x == y isn't the same as not (x /= y) for some
type,
[EMAIL PROTECTED] wrote:
G'day.
Quoting Janis Voigtlaender [EMAIL PROTECTED]:
Hmm, but I can easily define an instance of Eq that does not satisfy
this invariant. And I want the generated free theorem to be true for any
legal Haskell program.
I would think that if x == y isn't the same as
On 10/17/07, Janis Voigtlaender [EMAIL PROTECTED] wrote:
Okay, it is quite natural to take this stand. But as you say, there is
no such commitment in the language definition. And even if there were, I
doubt it would be possible to enforce such invariants in a compiler. So
there would be
G'day all.
Quoting Janis Voigtlaender [EMAIL PROTECTED]:
Okay, it is quite natural to take this stand. But as you say, there is
no such commitment in the language definition. And even if there were, I
doubt it would be possible to enforce such invariants in a compiler. So
there would be
On Thu, Oct 18, 2007 at 03:36:01AM -0400, [EMAIL PROTECTED] wrote:
(As an aside: The H98 report still list the right-zero law as being
a law for MonadPlus, even though most MonadPlus instances don't obey
it. That's actually a defect in the report.)
All the MonadPlus I can think of
Now that I look at it, the report notes that:
-- Note that (min x y, max x y) = (x,y) or (y,x)
but never says that this requirement is mandatory.
That's because the comment applies only to the default implementation,
not in general.
The report does require that The Ord class is used
On Thu, Oct 18, 2007 at 08:39:04PM -0400, David Menendez wrote:
On 10/18/07, Stefan O'Rear [EMAIL PROTECTED] wrote:
On Thu, Oct 18, 2007 at 03:36:01AM -0400, [EMAIL PROTECTED] wrote:
(As an aside: The H98 report still list the right-zero law as being
a law for MonadPlus, even though most
On 10/18/07, Stefan O'Rear [EMAIL PROTECTED] wrote:
On Thu, Oct 18, 2007 at 03:36:01AM -0400, [EMAIL PROTECTED] wrote:
(As an aside: The H98 report still list the right-zero law as being
a law for MonadPlus, even though most MonadPlus instances don't obey
it. That's actually a defect in
[Ccing to haskell-cafe; please direct any replies there instead of haskell]
G'day all.
First of all, once again well done to Sascha on a great tool.
Just a few comments.
Quoting Janis Voigtlaender [EMAIL PROTECTED]:
- support for type classes
(e.g., enter elem and note the generated
[EMAIL PROTECTED] wrote:
Some of these respects-restrictions arent as useful as they might be,
because they don't take into account easily-predictable invariants.
For example, the type:
(Eq a) = [a] - [a]
generates the following restriction:
g respects Eq if
forall x :: t1.
10 matches
Mail list logo
