kicad-developers team mailing list archive

[Dick Hollenbeck <dick@xxxxxxxxxxx>]

On 05/08/2014 01:31 PM, John Beard wrote:
> On 08/05/14 15:53, Dick Hollenbeck wrote:
>>
>>> That's exactly what I mean - older versions of KiCad should be able to 
>>> ignore, but retain, unknown data.
>>
>> This sentence has two concepts in it.  One is fools gold, the other is poorly expressed.
>>
>> 1) An older kicad should load a data file that is has never seen before.
> 
> Is this fools' gold? A PDF reader from 2005 would probably still load a
> PDF made by newer software, even if there are new features it cannot
> understand. It might say "You can't see the embedded 4D MegaContent
> (TM), upgrade to a version that support PDF spec v5.6 for that", but
> it will show you what it can. You'd be annoyed if it didn't, it would be
> like Flash needing the latest version to watch your video, without the
> excuse that is necessary to implement the latest and greatest DRM fad.
> 
>> The motivation should be that you want the flexibility to solve a specific problem.
> 
> The motivation is that I want the flexibility to add a field to a
> .kicad_mod file, that still allows someone else to read the footprint,
> if they don't *need* to know about that field. Currently, that will
> cause THROW_PARSE_ERROR(), and they get nothing.
> 
>> But it should not name future proofing as the motivation, because you don't want to
>> upgrade.  That's the part that gives me conceptual grief.
> 
> It's not because *I* don't want to upgrade, *I'm* to the one who's
> hypothetically extended some aspect of the footprint format for my own
> ends. It's because J. Random McTrunkBuild (or even his cousin,
> McDistroVersion) shouldn't need to recompile with a patch from me to
> read a footprint of mine which has my field "(user_sku 45443)" or
> "(jedec_ref "SOT45")" in it, when he doesn't need or care about that
> field.
> 
> The current state is there no way for people (not intimately familiar
> with the .kicad_mod format) downloading a footprint now to know if it's
> compatible with their KiCad without loading the footprint and then
> guessing that the "Expected...." message means the footprint contains
> unknown fields, as opposed to being malformed.
> 
> Forced recompiles are only free if your time is worthless and any
> problems caused by running bleeding-edge PCB software in production
> environments have zero cost.


Submit a patch.

Hope it gets accepted.