Re: gEDA-user: multiple attributes (was: [Patches] GTK Recent-file-manager)
>How would the dialog establish the order? Would the order be significant >to some action? If so, there should be a way to manipulate order from >the GUI. > As far as I can see, the only way for a program to distinguish between two attributes with the same name, attached to the same symbol is by the order that they appear in the symbol's attribute list. This is defined by the order in which they were attached to the symbol originally, or the order that they appear in the symbol file. As far as I know, none of the use cases that people have mentioned assign any meaning to the order in which the symbols appear in the list. It's possible for someone to write a script or netlister that does assign some meaning, but it doesn't seem like a good idea. Better to give different names to the attributes, like slotdef-A slotdef-B, etc. and have the code search for any attribute names beginning with "slotdef-". There _is_ a meaning to the order if a netlister expects only one attribute, but the symbol has several of the same name. In that case, the netlister could find either the first attribute of that name or the last, depending on how the netlister was written. About overloading: Sometimes it's desirable to overload attributes; for example I might want to simulate a circuit through a spice netlister, then generate a BOM of the parts in the simulation. Having the BOM netlister use the same "value" attributes as the simulation helps prevent errors in keeping the two flows in sync. To give the user the choice of overloading the symbols or not, each netlister could first look for a netlister-specific attribute, and if that doesn't exist then use a generic attribute. i.e first look for "spice-sdb-value", and if that doesn't exist then use the generic "value". ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: multiple attributes (was: [Patches] GTK Recent-file-manager)
Matthew Wilkins wrote: > Hm, Peter C is right that this complicates things a lot. Well, you asked for potential use cases. Not all conceivable uses may warrant the effort to code. In addition, there may be better ways to achieve the same goal. Symbols in gschem are a bit overloaded. The data base that has been floating on and off the mailing list is meant to better serve the purpose. An alternative would be the notion of "packages" like in other EDA suites. A package would be a container for whatever the designer of a library likes to bundle -- symbols, footprints, documents, notes, simulation models, and whatnot. > I *think* the list of attributes shown in the dialog can be > generated in a way where repeated attributes will appear as: > > documentation Vis N V > documentation (2) Vis N V > documentation (3) Vis N V How would the dialog establish the order? Would the order be significant to some action? If so, there should be a way to manipulate order from the GUI. ---<)kaimartin(>--- -- Kai-Martin Knaak Email: k...@familieknaak.de Öffentlicher PGP-Schlüssel: http://pool.sks-keyservers.net:11371/pks/lookup?search=0x6C0B9F53 ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: multiple attributes (was: [Patches] GTK Recent-file-manager)
>> What are typical use cases for having multiple same-named attributes in a >> symbol? >Same-named attributes in my symbols: >* slotdef -- this is pretty generic >* comment -- sometimes, more than one note needs to be delivered >* documentation -- sometimes, more than one datasheet is available >More use cases I can think of: >* author -- in case there is more than one. >* vendor -- where to buy Hm, Peter C is right that this complicates things a lot. I *think* the list of attributes shown in the dialog can be generated in a way where repeated attributes will appear as: documentation Vis N V documentation (2) Vis N V documentation (3) Vis N V Then when it comes time to apply a change, gschem will search the object's list of attributes to find the one that appears in the right sequence in the attribute list. >> While I was at it, I added a help button to the dialog, which brings up the >> 'Master Attributes List' of the wiki with definitions of all the typical >> attribute names. >Great. Is the list downloaded on the fly, or is it from a local copy? it uses the same mechanism as other help viewing actions, which read from the local copy. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: multiple attributes (was: [Patches] GTK Recent-file-manager)
On Jan 4, 2011, at 6:04 PM, Peter TB Brett wrote: > On Wednesday 05 January 2011 00:42:07 John Doty wrote: >> On Jan 4, 2011, at 5:22 PM, Matthew Wilkins wrote: >>> What are typical use cases for having multiple same-named attributes in a >>> symbol? >> >> A slotted symbol generally needs multiple slotdef attributes. >> >> A hierarchical symbol will have multiple source attributes if its >> underlying schematic has multiple pages. >> >> And nobody knows what other use cases there are, or may be in the future. >> You should make as few assumptions about how people will use attributes as >> practical. > > One of the problems we have at the moment is that sometimes attributes in the > schematic override attributes in the symbol, and sometimes they don't. > > Example 1. Suppose I have a "refdes=A?" attribute in a symbol. I instantiate > the symbol in a schematic, and attach a "refdes=A1" attribute to the > instantiated symbol. gnetlist (etc) will use "refdes=A1". This is > overriding > behaviour. > > Example 2. Suppose I have a "net=Vcc:1" attribute in a symbol. I instantiate > the symbol in a schematic, and attach a "net=Vdd:1" attribute to the > instantiated symbol. gnetlist will short Vcc to Vdd and connect pin 1 to the > shorted net. This is aggregation behaviour. > > The problem with this is inconsistency. IMHO it would be better to have > overriding behaviour *only*, because in the longer term being able to > reliably > override attributes would particularly be helpful in doing things like > hierarchical back-annotation and parameterised subcircuits (the latter would > be awesome for ASIC design applications, for instance). As far as I can > tell, > everything that can be achieved with aggregation behaviour can be achieved > with overriding behaviour, but not the other way around. This sort of inconsistent behavior is a serious barrier to extension of capability. I agree with this diagnosis. --- John Doty Noqsi Aerospace, Ltd. This message contains technical discussion involving difficult issues. No personal disrespect or malice is intended. If you perceive such, your perception is simply wrong. I'm a busy person, and in my business "go along to get along" causes mission failures and sometimes kills people, so I tend to be a bit blunt. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: multiple attributes (was: [Patches] GTK Recent-file-manager)
On Wednesday 05 January 2011 00:42:07 John Doty wrote: > On Jan 4, 2011, at 5:22 PM, Matthew Wilkins wrote: > > What are typical use cases for having multiple same-named attributes in a > > symbol? > > A slotted symbol generally needs multiple slotdef attributes. > > A hierarchical symbol will have multiple source attributes if its > underlying schematic has multiple pages. > > And nobody knows what other use cases there are, or may be in the future. > You should make as few assumptions about how people will use attributes as > practical. One of the problems we have at the moment is that sometimes attributes in the schematic override attributes in the symbol, and sometimes they don't. Example 1. Suppose I have a "refdes=A?" attribute in a symbol. I instantiate the symbol in a schematic, and attach a "refdes=A1" attribute to the instantiated symbol. gnetlist (etc) will use "refdes=A1". This is overriding behaviour. Example 2. Suppose I have a "net=Vcc:1" attribute in a symbol. I instantiate the symbol in a schematic, and attach a "net=Vdd:1" attribute to the instantiated symbol. gnetlist will short Vcc to Vdd and connect pin 1 to the shorted net. This is aggregation behaviour. The problem with this is inconsistency. IMHO it would be better to have overriding behaviour *only*, because in the longer term being able to reliably override attributes would particularly be helpful in doing things like hierarchical back-annotation and parameterised subcircuits (the latter would be awesome for ASIC design applications, for instance). As far as I can tell, everything that can be achieved with aggregation behaviour can be achieved with overriding behaviour, but not the other way around. Regards, Peter -- Peter Brett Remote Sensing Research Group Surrey Space Centre signature.asc Description: This is a digitally signed message part. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
