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Date: Wed, 14 Sep 2016 12:14:52 +0200 (CEST)
From: Roland Lutz <rlutz AT hedmen DOT org>
To: "Vladimir Zhbanov (vzhbanov AT gmail DOT com) [via geda-user AT delorie DOT com]" <geda-user AT delorie DOT com>
Subject: Re: [geda-user] Attribute namespaces (was: Can an attribute be
 attached to text for later inclusion in gnetlist backend?)
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Precedence: bulk

What makes using common "spice", "bom", and "pcb" namespaces attractive to 
me is that they are not defined by technical implementation details 
("What's the name of the backend I use?") but by a meaningful category 
("What's that attribute used for?") which is intuitively obvious to the 
user.

On Tue, 13 Sep 2016, Vladimir Zhbanov (vzhbanov AT gmail DOT com) [via 
geda-user AT delorie DOT com] wrote:
> Agreed, if the backends are compatible. I mean, e.g., that John Doty's 
> spice backend is not compatible with spice-sdb, IIUC. Otherwise we have 
> either to ensure they're compatible or to use separate namespaces.

I'm not so sure about that.  The spice-sdb and spice-noqsi backends aren't 
separate "problem domains" in the way SPICE simulation and PCB layout are; 
most people will probably pick one or the other and stick to it, at least 
within one project.  So the attributes can't conflict.

This could in theory be an issue with different PCB layout software, too, 
or even with one PCB layout software and different footprint libraries. 
What if someone wants to layout a schematic both in Osmond and pcb-rnd to 
see which software fits them best?

It would be possible to address this by adding optional "flavor" 
specifiers to the namespace, as in

     pcb[osmond]:footprint=
     pcb[pcb-rnd]:footprint=

However, I believe this is over-engineering a rare problem, and in reality 
the user would just have two different schematics, just like they would 
now.