ValueType.fromJson constructor

ValueType.fromJson(
  1. Object? json_
)

Returns a new instance from a JSON value. May throw if the value does not have the expected structure.

Implementation

factory ValueType.fromJson(Object? json_) {
  Object? json = json_;
  if (json is Map) {
    final MapEntry(:key, :value) =
        json.entries.firstWhere((e) => e.key != 'runtimeType');
    json = (
      key is int ? key : _spec.cases.indexWhere((c) => c.label == key),
      value,
    );
  }
  return switch (json) {
    (0, null) || [0, null] => const ValueTypeI32(),
    (1, null) || [1, null] => const ValueTypeI64(),
    (2, null) || [2, null] => const ValueTypeF32(),
    (3, null) || [3, null] => const ValueTypeF64(),
    (4, null) || [4, null] => const ValueTypeV128(),
    (5, final value) ||
    [5, final value] =>
      ValueTypeRef(RefType.fromJson(value)),
    _ => throw Exception('Invalid JSON $json_'),
  };
}