Kittinunf Result usage example

ResultUsage.kt

import com.github.kittinunf.result.*

open class AppError(message: String) : Throwable(message)
class ReadError(message: String) : AppError("Read error " + message)
class WriteError(message: String) : AppError("Write error " + message)

fun main(args: Array<String>) {

    val result: Result<Unit, AppError> = readArgs(args).flatMap { writeToConsole(it) }

    result.onSuccess { println("Success") }

    result.onFailure { error -> println("App Error " + error.message) }
}

private fun readArgs(args: Array<String>) = Result.of<Int, ReadError> {
    try {
        args.get(0).toInt() + args.get(1).toInt()
    } catch (e: Exception) {
        throw ReadError(e.message?:"")
    }
}


private fun writeToConsole(it: Int) = Result.of<Unit, WriteError> {
    try {
        println("result : " + it)
    } catch (e: Exception) {
        throw WriteError(e.message?:"")
    }
}