etting there :)
Cheers,
George
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G
ence can we use to cast False to 'a'.
>>
>>
>> In short, fundeps and type family dependencies only add
extra
>> unification constraints, which may help to resolve
ambiguous
>> types. They dont provide evidence. That's not to say
that they
>> couldn't. But you'
t;> Again, what evidence can we use to cast False to 'a'.
>>
>>
>> In short, fundeps and type family dependencies only add extra
>> unification constraints, which may help to resolve ambiguous
>> types. They don’t provide evidence. That's not to say that they
>
> Simon
>
>
> >
> > -Original Message-
> > From: Glasgow-haskell-users [mailto:glasgow-haskell-users-
> > boun...@haskell.org] On Behalf Of Wolfgang Jeltsch
> > Sent: 05 July 2017 01:21
> > To: glasgow-haskell-users@haskell.org
> > S
rom: Glasgow-haskell-users [mailto:glasgow-haskell-users-
| boun...@haskell.org] On Behalf Of Wolfgang Jeltsch
| Sent: 05 July 2017 01:21
| To: glasgow-haskell-users@haskell.org
| Subject: Trouble with injective type families
|
| Hi!
|
| Injective type families as supported by GHC 8.0.1 do n
Hi!
Injective type families as supported by GHC 8.0.1 do not behave like I
would expect them to behave from my intuitive understanding.
Let us consider the following example:
> {-# LANGUAGE RankNTypes, TypeFamilyDependencies #-}
>
> class C a where
>
> type T a = b | b -> a
>
> instance
