Thomas Jäger [EMAIL PROTECTED] writes:
I believe there may be some nasty interactions with generalized
newtype-deriving, since we can construct two Leibniz-equal types which
are mapped to different types using fundeps:
class Foo a where
foo :: forall f. f Int - f a
instance Foo
Simon,
I believe there may be some nasty interactions with generalized
newtype-deriving, since we can construct two Leibniz-equal types which
are mapped to different types using fundeps:
class Foo a where
foo :: forall f. f Int - f a
instance Foo Int where
foo = id
newtype Bar =
Einar
Good question. This is a more subtle form of the same problem as I
described in my last message. In fact, it's what Martin Sulzmann calls
the critical example. Here is a boiled down version, much simpler to
understand.
module Proxy where
class Dep a b | a - b
Hello,
On 8/11/05, Simon Peyton-Jones [EMAIL PROTECTED] wrote:
... Here is a boiled down version, much simpler to
understand.
module Proxy where
class Dep a b | a - b
instance Dep Char Bool
foo :: forall a. a - (forall b. Dep a b = a - b) - Int
