[elephant-devel] Status of Leslie's question and Sean's patch?

[Robert L. Read]

I haven't answered this because I've spent the last three days
trying to get Sean Ross's patch to work; the tests run green with it,
but if you run the tests again they fail.

The easiest way to answer this problem is to try it.

I may have to back out the changes that Sean sent in; they interact very
badly with the postmodern interface --- or at least the most recent
version of it.

I suspect that I may also be dealing with an SBCL bug of some kind in
the MOP.

I never set out to spend three days on this---the solution always seemed
to be right around the corner.



On Wed, 2007-12-19 at 10:50 +0100, Leslie P. Polzer wrote:
> The user's guide talks about added and discarded slots, but what's the behaviour
> when a slot changes?
> 
> Suppose I represent a picture with an object PIC that contains the location of
> a file holding it. I store a bunch of other objects that each have a picture:
> 
> (defpclass myobj ()
>   ((picture :type PIC)))
> 
> Now I decide later on that a string would be enough
> 
> (defpclass myobj ()
>   ((picture :type STRING)))
> 
> What will happen? A bad thing, i.e. a deserialization error?
> Is there a way to define how a PIC should be converted to a STRING?
> 
>   Leslie
>