Unboxed Vectors of newtype'd values

[Bas van Dijk]

On 5 June 2012 22:45, Simon Peyton-Jones <simonpj at microsoft.com> wrote:
> So Andres has explained how to do what Johan asks.  Does that mean that
> Bas’s problem is solved?

My problem can't be solved with GeneralizedNewtypeDeriving since a
UUID is not a newtype but an abstract data type defined in another
package[1].

However, the template-haskell from the vector-th-unbox package which
Reiner mentioned does the job perfectly:

derivingUnbox "UUID"
    [d| instance Unbox' UUID (Word32, Word32, Word32, Word32) |]
    [| \ uuid -> UUID.toWords uuid|]
    [| \ (a,b,c,d) -> UUID.fromWords a b c d |]

Thanks Reiner for pointing me to this package!

Cheers,

Bas

[1] http://hackage.haskell.org/packages/archive/uuid/latest/doc/html/src/Data-UUID-Internal.html#UUID