gEDA-dev: [pcb] attributes

[Ales Hvezda]

[snip]
>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.

	Yes. 

>
>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).

	I've thought about this more over the past few weeks, and
I am very much so in favor in reusing the existing unattached attribute
mechanism within gaf as the place for meta information (such as #2).
I am NOT in favor of using comments or such and having to create a
brand new language within .sch/.sym files.  The only thing that has to
be documented is the attribute names themselves and valid values/format.


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

	Unless somebody can think of a reason not to do this, I vote
yes on "unattached (toplevel) attributes can be and should be used to
hold meta information".  The real nice benefit to this is that all the
infrastructure (at least within gaf) is there to handle them and you
really do want this information inside to the specific design file you
were editing.

								-Ales