Chances of D getting proper runtime reflection?

[jdrewsen]

Den 23-08-2011 17:03, Jacob Carlborg skrev:
> On 2011-08-23 16:38, Andrei Alexandrescu wrote:
>> On 8/23/11 12:55 AM, Jacob Carlborg wrote:
>>> On 2011-08-23 08:52, Andrei Alexandrescu wrote:
>>>> On 8/22/11 11:30 PM, Jacob Carlborg wrote:
>>>>> Ok, then I just change "register" to a static method.
>>>>
>>>> A static method of whom?
>>>>
>>>> Andrei
>>>
>>> Well, "register" currently an instance method of Serializer so I would
>>> change it to be a static method of Serializer.
>>
>> I think the ability of a class to be serialized would be independent of
>> the notion of a serializer. To me, "this class is serializable" really
>> means "this class has metadata associated with it that allows interested
>> parties to serialize it". But perhaps this is splitting hairs.
>>
>> Andrei
>
> You don't want to have it in the class and don't want it in the
> serializer. I mean, it needs to be stored somewhere and I thought that a
> static method in Serializer would better than a completely global function.
>
> Are you thinking about having another serialization library that can use
> this information as well? I'm not sure if that's good idea, different
> serialization implementations might need to do very different things
> with the information.

It could be used for network transmissions. Correct me if I'm wrong but 
Orange serializes the entire object. When sending things over the 
network or when saving something to disk for that matter you most likely 
are only interested in serializing some of the fields of an object. I 
really think it would be nice to declaratively mark fields as 
serializable for certain purposes e.g.:

class Foo {
	int a;         // Send over network and saved to file
	int b;         // Saved to file
	ubyte[] cache; // not to be serialized
}

mixin(serialize!(Network, Foo, a);

mixin(serialize!(File, Foo, a);
mixin(serialize!(File, Foo, b);

// but still support not specifying each field
class Bar { int a; }
mixin(serialize!(File, Bar));


Another way would be to just declare a class as serializable and then 
for each serialization type (ie. Network, File) declare that they should 
skip a field. Actually I think I better like this approach since it 
would allow decoupling of serialization type and the declaration of 
serializability.

/Jonas