[deleted comment]

#jsonOn: has been implemented in the latest builds, but there is no default 
implementation for arbitrary objects. 
How about this for an default implementation:

Object>>jsonOn: aStream
    | attributes |
    attributes := Dictionary new.
    self class instVarNames do:
        [ :ivarName | 
        attributes 
            at: ivarName
            put: (self instVarNamed: ivarName) ].
    aStream json: attributes

See also: http://lists.squeakfoundation.org/pipermail/seaside/2010-
February/022484.html

I don't think that Seaside should provide an implementation for arbitrary 
objects:

- Every Javascript library requires objects to be represented in JSON 
differently. To avoid giving the illusion that 
there is only one possible representation I suggest to implement jsonOn: only 
on Dictionary, 
SequenceableCollection and the various literal types.

- #instVarNames and #instVarNamed: are platform specific methods.These method 
sends would need to go to a 
platform layer.

FYI, #instVarNamed: is on my list for addition to the latest Grease so it will 
be ok
shortly. #instVarNames was not planned so far.

I agree with your argument about arbitrary objects, though we do have to balance
"right" with "convenient". It does seem like the above encoding would only
*occasionally* be what you wanted... but I haven't done much JSON yet, so I may 
not
be the right one to speak to that. :)

I think there is a major refactoring needed here. The code is so ugly.

I think if we move these class-side encoder methods to the instance-side (why 
the heck are they on the class-
side anyway?) we sort of have a visitor that can be easily extended and changed 
in subclasses.

I guess my assumption is they were on the class-side so that they can be called 
with any Stream class. It looks 
like the JSStream is only needed if you want a String as the output (though why 
you can't just use a WriteStream 
on a string in that case, I have no idea).

Name: Javascript-Tests-Core-lr.49
Author: lr
Time: 2 February 2010, 10:55:20 pm
UUID: 8b845c12-6879-4e8c-b4cb-8f9fdece1fc9
Ancestors: Javascript-Tests-Core-BartGauquie.48

- merged changes of Bart Gauquie
- made JSJsonStream independent of JSStream, because that inheritance was 
rather inconvenient (delegate 
instead)

Name: Javascript-Pharo-Core-lr.5
Author: lr
Time: 2 February 2010, 10:49:23 pm
UUID: e4bc2c1d-0f22-4821-a25a-64e639994d79
Ancestors: Javascript-Pharo-Core-BartGauquie.4

- merged changes of Bart Gauquie
- made JSJsonStream independent of JSStream, because that inheritance was 
rather inconvenient (delegate 
instead)

Name: Javascript-Core-lr.76
Author: lr
Time: 2 February 2010, 10:48:43 pm
UUID: 30299522-954f-4101-b9b3-052d8db87152
Ancestors: Javascript-Core-BartGauquie.75

- merged changes of Bart Gauquie
- made JSJsonStream independent of JSStream, because that inheritance was 
rather inconvenient (delegate 
instead)

Issue 543 has been merged into this issue.