Oscar Finnsson wrote:
Anyone made a module/package that solves this problem already? I cannot be the first that needs generic type safe conversion... .
There's a restricted version in logfloat:Data.Numer.RealToFrac[1] which generalizes the Prelude's realToFrac to improve performance and correctness. To do much more than that you'll probably have to use something like Data.Data, Data.Typeable, or similar. Generally speaking, arbitrary casts from one type to another go against Haskell ideology because they don't make a lot of sense. Often times there are multiple intelligible ways to convert between two fixed types, so how can we choose? Things like realToFrac, read, show, etc make sense precisely because they are more restricted and therefore make explicit the semantic intentions of how the conversion should be done. [1] http://hackage.haskell.org/packages/archive/logfloat/0.12.1/doc/html/Data-Nu... -- Live well, ~wren