4 Nov
2014
4 Nov
'14
6:17 a.m.
On Mon, 3 Nov 2014, Edward Kmett wrote:
Haskell as a language and GHC as an implementation both lack a mechanism for 'explicitly forbidding the construction of an instance'.
In the links I sent, it is described how to achieve that with current available technology: https://ghc.haskell.org/trac/ghc/ticket/9334#comment:9
The badness of the abstraction, however, is not helped nor harmed by the existence of a Storable instance.
My point was, that Storable means "fixed size type", and thus it selects the inappropriate types from the Integral ones. As I said, there could be other big integer types where Ratio works, but they won't be Storable.