Re: gEDA-dev: [pcb] attributes

[Stuart Brorson <sdb-at-NOSPAMcloud9_dot_net>]

Guys,

> I just checked in a change that allows you to have pcb-global
> attributes and element-specific attributes in .pcb files:
>
> Attribute("name" "value")
>
> For global attributes, you can place these anywhere an Element is
> allowed.  For element-specific attributes, you can place them anywhere
> a Pin is allowed.
>
> PCB does nothing with these attributes; it only reads them, stores
> them, and writes them out later.

This leads me to a tangential riff on the following question:  Now
that both gschem and PCB have them, what is the purpose of these
unattached attributes?

Specifically, I can see two conceptually different uses for unattached
global attributes:

1.  They can hold information about the specific design element itself
(i.e. footprint, schematic page, etc).  For example, you can use an
unattached attribute to hold information about the author, the
licence, the date of creation, etc.

2.  They can hold information pertainent to the *tool*.  For
example, you can hold the last zoom setting of your gschem session,
the column widths and order for gattrib, etc.

I consider these two uses conceptually distinct.  My gut reaction is
to put information about the design itself (case 1) into the
unattached attribute held in the design file (.sch, .sym, .fp, or
.pcb).  On the other hand,, I would expect to put tool-related
meta-information (case 2) into a tool save file (.gattrib.sav or
pcb.settings or some such).

However, I perceive that others think that we can mix these two
classes of info into the unattached attributes held in the design
file.  I can think of no reason to not do it this way either.  I also
note that Apple's old file format stuck this kind of info into the
"resource fork" of the file, which is similar to embedding the info
into an unattached attribute.

Therefore, my question:  Is the intent of an unattached attribute to
hold tool-related meta information?  Is this what other programs do?

Thanks for your thoughts,

Stuart


_______________________________________________
geda-dev mailing list
geda-dev@moria.seul.org
http://www.seul.org/cgi-bin/mailman/listinfo/geda-dev