On 08/08/2010 01:39 PM, Jacob wrote:
On 8 aug 2010, at 17:27, Andrei Alexandrescu wrote:
Deserialize into Object and then cast the Object to Shape.
To be able to cast it to a Shape you need to know the type at compile
time when you deserialize it. Or you have to register a method that
deserializes the object, which is exactly how it works now when you
deserialize through a base class reference.
You only need to know the _base_ type statically.
Or would Variant be useful here? I have not used Variant.
Probably Variant would play a role when e.g. one wants to
deserialize "the next primitive type" without needing to know
exactly what type that is (e.g. different integer widths).
Andrei _______________________________________________ phobos
mailing list [email protected]
http://lists.puremagic.com/mailman/listinfo/phobos
I'm not sure if we understand each other correctly.
Most likely - sorry about that. Don't forget that all I'm going by is
the tutorial, which is very brief.
If you
deserialize into Object you eventually need to cast it to something
more useful and then you probably could have deserialized to that
type in the first place. The library can deserialize through base
class references (by register a deserialize method) but you would
have to start with a static type somewhere, not just Object. Do you
have a simple (code) example describing what you want to do?
I think the Shape example is simple enough to serve as a good baseline.
Say you have a hierarchy rooted in Shape including e.g. Triangle,
Circle, and Rectangle. Now say you have a drawing represented as a
Shape[]. What steps do you need to take to save the drawing to disk and
restore it later?
Andrei
_______________________________________________
phobos mailing list
[email protected]
http://lists.puremagic.com/mailman/listinfo/phobos
