[Haskell-beginners] Convert my own types to the Haskell types using typeclass
kd6ck at virginia.edu
Fri Apr 11 20:15:48 UTC 2014
Thank you very much!
That is exactly what I want.
On Fri, Apr 11, 2014 at 2:43 PM, Magnus Therning <magnus at therning.org>wrote:
> On Fri, Apr 11, 2014 at 12:50:45PM -0400, ke dou wrote:
> > instance Coercible (MyOption a) where
> > type Return (MyOption a) = Prelude.Maybe a
> > toHaskell (Some a) = Prelude.Just a
> > toHaskell None = Prelude.Nothing
> The basic issue has been solved in another thread, but wouldn't you
> want this one to be something like this:
> instance Coercible a => Coercible (MyOption a) where
> type Return (MyOption a) = Prelude.Maybe (Return a)
> toHaskell (Some a) = Prelude.Just (toHaskell a)
> toHaskell None = Prelude.Nothing
> Magnus Therning OpenPGP: 0xAB4DFBA4
> email: magnus at therning.org jabber: magnus at therning.org
> twitter: magthe http://therning.org/magnus
> What gets measured, gets done.
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