The numeric c types are (effectively) integral, too.
Henning Thielemann
lemming at henning-thielemann.de
Wed Mar 27 17:16:09 CET 2013
On Wed, 27 Mar 2013, Jeff Shaw wrote:
> On Wednesday, March 27, 2013 11:30:24 AM, Henning Thielemann wrote:
>
>> I don't think that an Integral instance is the right way
>> to go, since it would imply the signature:
>>
>> div :: CTime -> CTime -> CTime
>>
>> and the quotient of two time values is not a time.
>
> That is irrelevant.
It is highly relevant and certainly a major difference between Haskell and
C. A time can be represented with any unit and with either integer or
floating or fixed-point numbers. Actually, the integer can always be read
as fixed-point number, since the unit is somehow arbitrary. The quotient
of two time values is not a time value but a scalar value and it is good
if Haskell alerts you when you mix them up.
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