Dimensional analysis with fundeps (some physics comments)
Terrence Brannon
princepawn@earthlink.net
Tue, 1 May 2001 18:28:28 -0700
Excuse me for playing referee here, as I am looking at this discussion
from a very abstract level, as I am a beginning functional-logic
programmer. But my question (primarily for Fergus) is: "has Ashley
shown in her example a means of automating a toUnits imperative in
Haskell that must be done explicitly in Mercury?" If so, then we have
the start of the Haskell-Mercury comparison document which shows an
advantage of Haskell over Mercury.
> I'm cross-posting this to the Libraries list...
>
> At 2001-04-10 18:02, Fergus Henderson wrote:
>
> >Still, the need to insert explicit `toUnits' is
> >annoying, and it would be nice to have a system where every number was
> >already a dimensionless unit.
>
> That's easy:
>
> --
> type Unit rep = Dimensioned Zero Zero Zero rep;
>
> instance (Real a) => Real (Unit a) where
> {
> -- put instances here
> };
> --
>
> Of course you'll have to appropriately declare superclasses of Real, such
> as Num, Ord, Show, Eq etc.
>
> --
> Ashley Yakeley, Seattle WA
>
>
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