Re: Dimensional analysis with fundeps (some physics comments)
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
I'm cross-posting this to the Libraries list...
I'm not sure that's an appropriate thing to do. As I understand it, the libraries list is concerned with libraries which are currently in the standard, or that are getting stable enough to either add to the standard or for some non-singular set of compilers to officially support. OTOH, the dimensional analysis stuff is not a library, not a proposed library and, since it seems to be less than a week old, not approaching stability. -- Alastair Reid
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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participants (3)
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Alastair Reid -
Ashley Yakeley -
Terrence Brannon