emptyAsync method
Implementation
Future<bool> emptyAsync() async {
final rval =
cvRunAsync<bool>((callback) => cffi.CascadeClassifier_Empty_Async(ref, callback), (c, p) {
final rval = p.cast<ffi.Bool>().value;
calloc.free(p);
return c.complete(rval);
});
return rval;
}