Re: [Haskell-cafe] Announce: EnumMap-0.0.1

On Wed, Aug 12, 2009 at 2:09 AM, Ketil Malde wrote:

Felipe Lessa writes:

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There are some funky Enum instances around:

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IMO it's implicit that keys overwrite eachother whenever their 'fromEnum' is equal, however that may be spoken in the docs.

I couldn't find anything explicit in the documentation.  I'd suggest a clear note at the top, dismissing the (IMO natural) notion that "EnumMap k v" behaves like "Map k v" (which was true for IntMap and Map Int, I believe).

I haven't updated any of the documentation from IntMap over s/IntMap/EnumMap/g.

And perhaps also note that you will get exceptions for values outside the Enum range.

I'd think that part is obvious.

It strikes me that using Bits instead of Enum might be more likely to be what people want in many cases - but perhaps that would be too slow? Also that Enum really should map to Integer, but again, that's a speed issue.¹

I think Enum is a little more natural--perhaps I'm wrong.