Decodable<T> class abstract interface

An object that can decode a value of type T from various data formats.

The interface can be used like this:

class PersonDecodable implements Decodable<Person> {
  const PersonDecodable();

  @override
  Person decode(Decoder decoder) {
    /* ... */
  }
}

The Decodable interface can be used for any type, including first-party types, core or third-party types.

Objects implementing Decodable can decode values to various data formats using the respective T from<Format>(data) extension method. A particular method is available by importing the appropriate library or package:

final Decodable<Person> personDecodable = const PersonDecodable();

// From 'package:codable/json.dart'
final Person person = personDecodable.fromJson('...');

// From 'package:codable/standard.dart'
final Person person = personDecodable.fromMap({...});

// From imaginary 'package:x/x.dart'
final Person person = personDecodable.fromX(x);

See also:

• Encodable for encoding values to various data formats.
• Codable for combining both encoding and decoding of types.