[Haskell] Haskell type containing no non-_|_ values?

Janis Voigtlaender voigt at tcs.inf.tu-dresden.de
Fri Mar 26 14:06:36 EST 2004

Tomasz Zielonka wrote:
> On Fri, Mar 26, 2004 at 01:56:04PM +0100, Tomasz Zielonka wrote:
> >
> > I don't know if you can have both 'no newtype' and 'haskell 98'
> > satisfied.
> Ross Paterson provided a solution using data.

I didn't yet see that solution since I receive Haskell mails in digest
mode. Anyway, "Haskell 98" is not a must. What I would want is a type
that doesn't need additional declarations, be it newtype or data.
"forall a. a" has this property, a pre-defined type would also have this
property. BTW, what is the reason for not allowing (forall a. a) as part
of a tuple?

Ciao, Janis.

Janis Voigtlaender
mailto:voigt at tcs.inf.tu-dresden.de

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