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From: Jacob Sparre Andersen <sparre@crs4.it>
Newsgroups: comp.lang.ada
Subject: Macks - adding unit constants?
Date: Thu, 09 Oct 2003 09:57:32 +0200
Organization: CRS4, Center for Adv. Studies,
 Research and Development in Sardinia
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Date: 2003-10-09T06:42:10+00:00
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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."