[Haskell-cafe] Custom Enum instance with non-consecutive indices

Nicolas Trangez nicolas at incubaid.com
Sat Nov 17 16:23:28 CET 2012

On Sat, 2012-11-17 at 16:52 +0200, Roman Cheplyaka wrote:
> Hi Nicolas,
> The simplest approach would be to use the standard (derived) Enum
> instance that would be used for enumerations (like [Flag1..]), and
> have your own functions to convert to/from magic constants. 

Sure, but that kind-of defeats the purpose... fromEnum/toEnum would then
return some nonsensical integer value.


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