flatMap<R extends Object> method

@override Async<R> flatMap<R extends Object>(@noFutures Resolvable<R> noFutures(T value))

Chains another Resolvable-producing operation: the monadic bind for Resolvable. If this is in an Err state, the chain short-circuits with that Err. If noFutures throws, the throw is absorbed into an Err.

Equivalent to .then(...) followed by .flatten(), with the short-circuit and throw-absorption wired in.

Implementation

@override
@pragma('vm:prefer-inline')
Async<R> flatMap<R extends Object>(
  @noFutures Resolvable<R> Function(T value) noFutures,
) {
  return Async<R>(() async {
    final result = await value;
    switch (result) {
      case Ok(value: final v):
        return await noFutures(v).unwrap();
      case final Err<T> err:
        throw err;
    }
  });
}