Sealed class to pass different states from a repository implementation or saving different state of a variable. Very useful when working with network calls or any other data source or single source of truth principle.

ResultData.kt

sealed class ResultData<out T> {
    object Loading : ResultData<Nothing>()
    data class Success<out T>(val data: T) : ResultData<T>()
    data class Error(val throwable: Exception? = null, val message: String? = null) :
        ResultData<Nothing>()

    fun isLoading() = this is Loading
    fun isSuccess() = this is Success
    fun isError() = this is Error
}