The file builtins\json.e (not an autoinclude) contains a simple json parser/printer/converter.

Use parse_json() to convert a string representation of a JSON object (see http://json.org for a formal definition, such as it is) to an internal form suitable for further processing.
Details of the internal form can be found on the parse_json page.

Use print_json() to convert an internal form into a string representation of a JSON object.

Some examples can be found in demo/rosetta/JSON.exw.

Note this does not enforce json string contents:
\-prefixes are not enforced (esp /)
\uHHHH by pure happy coincidence matches phix native format, no more.
Unicode as utf8 is considered sufficient; no utf-16 surrogate pair stuff.

Performance note/disclaimer

No particular effort has been made regarding performance. (Keeping things dirt-simple is deemed a better goal.)
I would strongly expect the actual conversion to be almost completely IO bound, however for very large json objects that require significant processing, there may be a case for indexing the internal form - but that should be reasonably straightforward and is deemed outside the responsibility of these routines. It would also be fair to say that the trim_res argument is lazily implemented, and it might be better not to add any whitespace in the first place, instead of trimming it away at the last moment.

Compatibility note

OpenEuphoria cannot distinguish between {} and "" and consequently may accept some things (specifically the first of those) as valid that Phix does not. Phix will reject {12} as invalid, because it is not a string, whereas OE will treat it as "\x0C". Otherwise this component should run on both Phix and OpenEuphoria.

The following constants are defined in builtins\json.e (see parse_json for more details):
global constant JSON_OBJECT = -1,
                JSON_ARRAY = -2, 
                JSON_KEYWORD = -3,
                JSON_INVALID = -4