[Haskell-cafe] (newbie) instance Enum MyType where, smarter way?
sven.panne at aedion.de
Tue Mar 27 11:42:22 EDT 2007
On Tuesday 27 March 2007 17:15, Adrian Neumann wrote:
> Which doesn't work because succ and pred are not (properly?) defined. Is
> there a way to let deriving Enum do *some* of work (i.e. defining succ
> and pred) while manually defining the other functions?
Hmmm, this seems to be a confusing usage of the Enum class, e.g. 'fromEnum .
toEnum' changes some values (allowed by the report, but confusing
nevertheless). Using Data.Bits.Bits somehow could be a better option, but one
has to know more about your use case.
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