ch := make(chan itemOrErr[string])

	go func() {
		defer xioutil.SafeClose(ch)

		// Allocate new results channel to receive ObjectInfo.
		objInfoCh := make(chan itemOrErr[ObjectInfo])

		if err := objAPI.Walk(ctx, minioMetaBucket, pathPrefix, objInfoCh, WalkOptions{}); err != nil {
			select {
			case ch <- itemOrErr[string]{Err: err}:
			case <-ctx.Done():

	wk, err := workers.New(workerSize)
	if err != nil {
		// invalid worker size.
		return err
	}

	retryAttempts := ri.RetryAttempts
	ctx, cancel := context.WithCancel(ctx)

	results := make(chan itemOrErr[ObjectInfo], 100)
	if err := api.Walk(ctx, r.Bucket, r.Prefix, results, WalkOptions{
		Marker: lastObject,
		Filter: selectObj,
	}); err != nil {
		cancel()

	// Walk lists all objects including versions, delete markers.
	Walk(ctx context.Context, bucket, prefix string, results chan<- itemOrErr[ObjectInfo], opts WalkOptions) error

	// Object operations.

	// GetObjectNInfo returns a GetObjectReader that satisfies the
	// ReadCloser interface. The Close method runs any cleanup

	}

	wk, err := workers.New(workerSize)
	if err != nil {
		// invalid worker size.
		return err
	}

	ctx, cancel := context.WithCancel(ctx)
	defer cancel()

	results := make(chan itemOrErr[ObjectInfo], workerSize)
	if err := api.Walk(ctx, r.Bucket, r.Prefix, results, WalkOptions{
		Marker:       lastObject,
		LatestOnly:   false, // we need to visit all versions of the object to implement purge: retainVersions

	select {
	case <-ctx.Done():
		return ctx.Err()
	case <-time.After(d):
	}
	return nil
}

// helper type to return either item or error.
type itemOrErr[V any] struct {
	Item V
	Err  error
}

func filterStorageClass(ctx context.Context, s string) string {
	// Veeam 14.0 and later clients are not compatible with custom storage classes.