anchor.diff:  ///
   /// Shorthand for `json.encode`. Useful if a local variable shadows the global
   /// [json] constant.
  +///
  +/// Example:
  +/// ```dart
  +/// const data = {'text': 'foo', 'value': 2, 'status': false, 'extra': null};
  +/// final String jsonString = jsonEncode(data);
  +/// print(jsonString); // {"text":"foo","value":2,"status":false,"extra":null}
  +/// ```
  +///
  +/// Example of converting an otherwise unsupported object to a
  +/// custom JSON format:
  +///
  +/// ```dart
  +/// class CustomClass {
  +///   final String text;
  +///   final int value;
  +///   CustomClass({required this.text, required this.value});
  +///   CustomClass.fromJson(Map<String, dynamic> json)
  +///       : text = json['text'],
  +///         value = json['value'];
  +///
  +///   static Map<String, dynamic> toJson(CustomClass value) =>
  +///       {'text': value.text, 'value': value.value};
  +/// }
  +///
  +/// void main() {
  +///   final CustomClass cc = CustomClass(text: 'Dart', value: 123);
  +///   final jsonText = jsonEncode({'cc': cc},
  +///       toEncodable: (Object? value) => value is CustomClass
  +///           ? CustomClass.toJson(value)
  +///           : throw UnsupportedError('Cannot convert to JSON: $value'));
  +///   print(jsonText); // {"cc":{"text":"Dart","value":123}}
  +/// }
  +/// ```
   String jsonEncode(Object? object,
           {Object? toEncodable(Object? nonEncodable)?}) =>
       json.encode(object, toEncodable: toEncodable);
  
positive.code: }
  
  /// This class converts JSON objects to strings.
  class JsonEncoder extends Converter<Object?, String> {
    /// The string used for indention.
    ///
  
negative.code: ///
  /// A JSON input must be the JSON encoding of a single JSON value,
  /// which can be a list or map containing other values.
  ///
  /// Throws [FormatException] if the input is not valid JSON text.
  ///
  /// Example:
  /// ```dart
  /// const JsonDecoder decoder = JsonDecoder();
  ///
  /// const String jsonString = '''
  ///   {
  ///     "data": [{"text": "foo", "value": 1 },
  ///              {"text": "bar", "value": 2 }],
  ///     "text": "Dart"
  ///   }
  /// ''';
  ///
  /// final Map<String, dynamic> object = decoder.convert(jsonString);
  ///
  /// final item = object['data'][0];
  /// print(item['text']); // foo
  /// print(item['value']); // 1
  ///
  /// print(object['text']); // Dart
  /// ```
  ///
  /// When used as a [StreamTransformer], the input stream may emit
  /// multiple strings. The concatenation of all of these strings must
  