code: function _RDFToObject(o, useNativeTypes) {
    // convert IRI/blank node object to JSON-LD
    if(o.type === 'IRI' || o.type === 'blank node') {
      return {'@id': o.value};
    }
  
    // convert literal to JSON-LD
    var rval = {'@value': o.value};
  
    // add language
    if('language' in o) {
      rval['@language'] = o.language;
    }
    // add datatype
    else {
      var type = o.datatype;
      // use native types for certain xsd types
      if(useNativeTypes) {
        if(type === XSD_BOOLEAN) {
          if(rval['@value'] === 'true') {
            rval['@value'] = true;
          }
          else if(rval['@value'] === 'false') {
            rval['@value'] = false;
          }
        }
        else if(_isNumeric(rval['@value'])) {
          if(type === XSD_INTEGER) {
            var i = parseInt(rval['@value']);
            if(i.toFixed(0) === rval['@value']) {
              rval['@value'] = i;
            }
          }
          else if(type === XSD_DOUBLE) {
            rval['@value'] = parseFloat(rval['@value']);
          }
        }
        // do not add native type
        if([XSD_BOOLEAN, XSD_INTEGER, XSD_DOUBLE, XSD_STRING]
          .indexOf(type) === -1) {
          rval['@type'] = type;
        }
      }
      else if(type !== XSD_STRING) {
        rval['@type'] = type;
      }
    }
  
    return rval;
  }
docs: Converts an RDF triple object to a JSON-LD object.
  
  @param o the RDF triple object to convert.
  @param useNativeTypes true to output native types, false not to.
  
  @return the JSON-LD object.