Proposal: Show and Read for Data.Ord.Down

Ivan Lazar Miljenovic ivan.miljenovic at
Fri Oct 11 23:15:07 UTC 2013

On 26 September 2013 18:03, David Luposchainsky
<dluposchainsky at> wrote:
> On 2013-09-26 06:50, Edward A Kmett wrote:
>> I strongly favor creating instances like this.
>> Not having them just makes the world more painful to debug code to
>> make a normative point and leads to greater code fragmentation when
>> someone else has another stance.
> I agree. Being able to look at some value "the dirty way" is an
> important use case of Show (be it as a return value or via trace), and I
> see no reason for any datatype to not support Show when it could.
> On Read I don't have an opinion because I usually try to avoid it :-)
> +1

+1 from me as well; furthermore, how about an "unDown :: Down a -> a"
record function or some such just to avoid the "\(Down x) -> x" usage
like how Krzysztof described?

Ivan Lazar Miljenovic
Ivan.Miljenovic at

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