tommd / fixedpoint Goto Github PK

Hi. Thank you for your convenient package.

Could you help me?
I want to use odd, big word type(for example, Word65).
So I thought that a combination of your package and OddWord package is good for it.
The following code is the one I tried.

module Example where
import Data.Word
import Data.Word.Odd
import Data.FixedPoint

type Word65 = BigWord Word1 Word64
a = 1 :: Word65

and encountered the following error

No instance for (Data.Bits.FiniteBits (OddWord Word8 (One ())))
  arising from the literal ‘1’
In the expression: 1 :: Word65
In an equation for ‘a’: a = 1 :: Word65

If you use Word8 instead of Word1, no error.
I wonder that Word1 and Word64 are certainly instances of Num but Word65 may not be an instance of Num.

How can I avoid this problem?

Can we use a newtype constructor for GenericFixedPoint? Can be convenient to use e.g. coerce, plus the performance benefits associated with newtypes

Thanks,
Will