Macks - adding unit constants?

[Jacob Sparre Andersen <sparre@crs4.it>]

I have just started to use Macks to generate packages for handling 
physical units.  I like the tool, but I would appreciate some method for 
handling different proportional units like km, m and mm _in_ Macks.  I 
also find writing:

    Diameter := 3.0 * mm;
    Diameter := 0.003 * m;

more appealing than:

    Diameter := 0.003;
    Diameter := Meter (0.003);

I considered if changing the declaration of fundamental units from:

    Meter is fundamental;

to:

    Meter is fundamental Length;

naming the type "Length" and not "Meter", but declaring a constant 
"Meter" of type "Length".

Since "Unit * Integer" is reserved for declaring vectors, we need some 
other syntax for declaring derived units.  Could:

    mm := 0.001 * Meter;

be used?  Or should I just put the derived units in a separate package?

Jacob
-- 
"There is nothing worse than having only one drunk head."