Re: [boost] [Review][PQS] Physical Quantities

From: Pavel Vozenilek (pavel_vozenilek_at_[hidden])
Date: 2006-06-05 12:28:45

"Andy Little" wrote:

>>Further, this may or
>> not be the right place for this and I know you are big on the SI or 
>> similar
>> units but has there been any consideration to adding monetary types. The
>> requirements would be a monetary base class with specializations for
>> dollars, pounds, euros and expandable to any type of currency. The 
>> further
>> needs to be a global, static or facet, that is replaceable and stores the
>> conversion factors that way it could have a default text file 
>> implementation
>> that could be replaced with an database implementation.
>
> One reason the PQS cant handle money units is that their relationship isnt
> constant or even necessarily agreed upon by any two different authorities 
> at one
> time. Physical quantities have nominally constant conversion factors. That
> impacts in the way the library can do a lot of computations at compile 
> time. I
> know this issue comes up a lot. Why is money not a physical quantity. I 
> dont
> really have an answer, except to say that I the SI  dont consider money to 
> be a
> physical quantity.
>
> There must also be a need for a type that works out (say) the cost of 
> applying
> paint to a certain area. Its another field that PQS could be expanded 
> into. The
> scope of that library is potentially very wide of course!
>

There was at least one massive thread about hypothetical
boost::money library, year or so ago.

My impression was that such tool could be potentionally
something even larger than current pqs.

/Pavel