JSON parsing and serialization for maps.
parse(s str) -> {str: any} | error: Parses a JSON object into a map, preserving nested lists, maps, numbers, booleans, andnull.stringify(data {str: T}) -> str | error: Serializes a Nimble value tree to JSON.pretty(data {str: T}) -> str | error: Pretty-prints JSON.
load json
cfg = json.parse('{"env":"dev","port":8080}')?
out(cfg["env"])