Serialization for D. Comments, please!

[BCS]

Hello grauzone,

> BCS wrote:
> 
>>>> Well, I can switch the default but, in my experience, most of the
>>>> time repetition doesn't matter. I also dissagree on the "relatively
>>>> useless
>>>> 
>>> Oh really?
>>> 
>> I haven't used a graph data structure in some time. Most of them have
>> been trees. And the cases I can think of, the repeated reference bit
>> has been central the the structure so the chances of getting it wrong
>> (or of missing it under test) are about nil.
>> 
> IMO, most tree-like structures are still full graphs in memory,
> because they often contain "parent" pointers, or point back to a
> parent indirectly (e.g. even if a generic tree data structure is
> implemented without parent pointers, the data element itself might
> contain such pointers).

I'm referring to data structure that I could add serialization to, e.i. ones 
where I would know of they have parent references. I still stand by my assertion.

> 
>> OTOH pointers to struct are not value types...
>> 
> Pointers are a whole different thing. A pointer can still point to a
> "value" type, because that struct might be embedded within an object
> (a class member that's a struct).
> 

pointers to members won't be supported any time soon.

>>>> interfaces are not supported either.
>>>> 
>>> But supporting interfaces would be very simple.
>>> 
>> It wouldn't be hard in the current form (you would add a mixin to the
>> interface as well) but the non-mixin, outside in approach would have
>> all sorts of interesting issues like how to get the correct
>> sterilizer function.
>> 
> Huh? You can simple cast the interface to an object.

That is not safe. not all interface instances are D objects.

> And then cast the
> object to the serializeable type.

Cast only works if you know /at compile time/ what type to cast to so I don't 
think that's going to work. 

> You need to be able to do that
> anyway, because object references can be of the type "Object", and
> there's no way you'd add your serialize mixin to Object.

And that just brought up another issue: how do you serialize a class that 
only ever shows up as a base class reference? The lib has no way to /find/ 
the type at compile time so it has no way to generate code to deal with it.

> 
> Also, is you writing "sterilizer" a typo or not?

typo (is it in the lib or just this thread?) I'd be even worse without a 
spellchecker :(