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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