JsonCodec constructor Null safety

const JsonCodec(
  1. {Object? reviver(
    1. Object? key,
    2. Object? value
    )?,
  2. Object? toEncodable(
    1. dynamic object
    )?}
)

Creates a JsonCodec with the given reviver and encoding function.

The reviver function is called during decoding. It is invoked once for each object or list property that has been parsed. The key argument is either the integer list index for a list property, the string map key for object properties, or null for the final result.

If reviver is omitted, it defaults to returning the value argument.

The toEncodable function is used during encoding. It is invoked for values that are not directly encodable to a string (a value that is not a number, boolean, string, null, list or a map with string keys). The function must return an object that is directly encodable. The elements of a returned list and values of a returned map do not need to be directly encodable, and if they aren't, toEncodable will be used on them as well. Please notice that it is possible to cause an infinite recursive regress in this way, by effectively creating an infinite data structure through repeated call to toEncodable.

If toEncodable is omitted, it defaults to a function that returns the result of calling .toJson() on the unencodable object.

Implementation

const JsonCodec(
    {Object? reviver(Object? key, Object? value)?,
    Object? toEncodable(dynamic object)?})
    : _reviver = reviver,
      _toEncodable = toEncodable;