func serviceFunc(b *Brain, used, missing *dep.Set) func(...string) ([]*dep.HealthService, error) {
	return func(s ...string) ([]*dep.HealthService, error) {
		result := []*dep.HealthService{}

		if len(s) == 0 || s[0] == "" {
			return result, nil
		}

		d, err := dep.NewHealthServiceQuery(strings.Join(s, "|"))
		if err != nil {
			return nil, err
		}

		used.Add(d)

		if value, ok := b.Recall(d); ok {
			return value.([]*dep.HealthService), nil
		}

		missing.Add(d)

		return result, nil
	}
}
func serviceFunc(b *Brain, used, missing *dep.Set) func(...string) ([]*dep.HealthService, error) {
	return func(s ...string) ([]*dep.HealthService, error) {
		result := []*dep.HealthService{}

		if len(s) == 0 || s[0] == "" {
			return result, nil
		}

		d, err := dep.NewHealthServiceQuery(strings.Join(s, "|"))
		if err != nil {
			return nil, err
		}

		used.Add(d)

		if value, ok := b.Recall(d); ok {
			return value.([]*dep.HealthService), nil
		}

		missing.Add(d)

		return result, nil
	}
}
// serviceFunc returns or accumulates health service dependencies.