[boost] Re: Physical Quantities revisited

From: Hugo Duncan (hugoduncan_at_[hidden])
Date: 2003-10-27 10:16:56

Ross MacGregor <ross__macgregor_at_[hidden]> wrote:
> Hugo Duncan wrote:
>> Trying to encode the conversion factors into the type signature
>> seems ugly to me. Unit conversion takes place from one unit to another
>> and this can be expressed directly (untested code below).
>
> Would this lead to an explosion of converters?

I was just trying to define an interface.  The interface could be
implemented as you describe below.

> My original idea was each unit would define its relationship to the 
> standard SI unit. Therefore the transform algorithm will need to work 
> both ways:
>
> meter -> T() -> kilometer
> kilometer -> -T() -> meter
>
> Convertion between two units would then require a two step precess.
>
> kilometer -> -T() -> meter -> T() -> centimeter