I have a not totally useless Perl implementation of JSYNC.pm on CPAN and GitHub now.
It is passing these 6 data driven roundtripping tests, which should be easily grokkable:
Here is the (reasonably small amount of) source code:
It has a dump() and a load() function. dump() takes a Perl object, makes a full clone in the JSYNC/JSON style, and JSON encodes it. load() takes a JSYNC string, JSON decodes it, and makes a full clone to a native Perl object.
The full clone in both directions seems a bit heavy handed, but I think it is too soon to make premature optimizations. I want to get a common test suite passing in several languages, and then think about optimization refactoring.
The tests point out that it might be a good time to revisit the default tags for objects. Having the term 'perl' in there will surely not pass on Python, etc. The Python defaults are also not portable.