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encoder property
    override
   
  Returns the encoder from S to T.
It may be stateful and should not be reused.
Implementation
JsonEncoder get encoder {
  if (_toEncodable == null) return const JsonEncoder();
  return JsonEncoder(_toEncodable);
}© 2012 the Dart project authors
Licensed under the BSD 3-Clause "New" or "Revised" License.
 https://api.dart.dev/stable/2.18.5/dart-convert/JsonCodec/encoder.html