Proposal: Num instance for tuples

wren ng thornton wren at freegeek.org
Tue Oct 23 06:41:41 CEST 2012


On 10/19/12 7:29 AM, Simon Marlow wrote:
> On 18/10/2012 11:07, Henning Thielemann wrote:
>>
>> On Thu, 18 Oct 2012, Twan van Laarhoven wrote:
>>
>>> One piece of utility code that I find myself writing over and over
>>> again is the pointwise Num instance for tuples, i.e.
>>
>> For my taste, writing
>>
>>    2 :: (Int, Integer)
>>
>>    abs (x,y)
>>
>> should yield a compiler error and the compiler should not try to
>> interpret it in some way. For the cases where you need these instances I
>> suggest you use custom data types.
>
> Agreed, -1 from me.

Agreed, another -1.

-- 
Live well,
~wren



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