My work on JSON parsing doesn’t cover the full JSON grammar.
And the task of “translating” any JSON document to an XML document doesn’t have a solution. There are JSON constructs, which cannot be translated to XML without defining additional conventions and introducing additional elements — so the final XML structure isn’t a true and natural representation of the original JSON object.
In XSLT 3.0 there is a function to parse any JSON object — parse-json() — to a map — a new data type introduced in XSLT 3.0. Read about this here:
http://www.w3.org/TR/xslt-30/#json