r4WalkFhirPath function
Implementation
List<dynamic> r4WalkFhirPath(
  r4.Resource? resource,
  String pathExpression, [
  Map<String, dynamic>? environment,
]) {
  final resourceJson = resource?.toJson();
  return walkFhirPath(
    context: resourceJson,
    pathExpression: pathExpression,
    environment: environment,
    version: FhirVersion.r4,
  );
}