• A JSON object is mapped to a term json(NameValueList), where NameValueList is a list of Name=Value. Name is an atom created from the JSON string.
• A JSON array is mapped to a Prolog list of JSON values.
• A JSON string is mapped to a Prolog atom
• A JSON number is mapped to a Prolog number
• The JSON constants true and false are mapped -like JPL- to @(true) and @(false).
• The JSON constant null is mapped to the Prolog term @(null)

Here is a complete example in JSON and its corresponding Prolog term.

{ "name":"Demo term",
  "created": {
    "day":null,
    "month":"December",
    "year":2007
  },
  "confirmed":true,
  "members":[1,2,3]
}

json([ name='Demo term',
       created=json([day= @null, month='December', year=2007]),
       confirmed= @true,
       members=[1, 2, 3]
     ])

The following options are processed:

null(+NullTerm)

Term used to represent JSON null. Default @(null)

true(+TrueTerm)

Term used to represent JSON true. Default @(true)

false(+FalseTerm)

Term used to represent JSON false. Default @(false)

end_of_file(+ErrorOrTerm)

If end of file is reached after skipping white space but before any input is processed take the following action (default error):

• If ErrorOrTerm == error, throw an unexpected end of file syntax error
• Otherwise return ErrorOrTerm.

Returning an status term is required to process Concatenated JSON. Suggested values are @(eof) or end_of_file.

value_string_as(+Type)

Prolog type used for strings used as value. Default is atom. The alternative is string, producing a packed string object. Please note that codes or chars would produce ambiguous output and are therefore not supported.

See also

json_read_dict/3 to read a JSON term using the version 7 extended data types.