I understand how these monads work

They have a cost

First you need to

flatMap

everything, and wrap callers and callees too

yes, that true

I prefer to guarantee that a variable is legit and then use it "naked" rather than having all my code dealing with that value inside a monad

oh i see

x.canThrow()
x.operation()  // guarantee to succeed, otherwise would have thrown

vs

val t = Try<...>
t.flatMap { it.operation() }
t.flatMap { it.operation2() }

what about unchecked exception. Sometimes i not really know that a method will throw certain exception. especially when the method not force us to use try-catch

Yeah unchecked are a pain to deal with

for me this is more readable.

return gradingRequestTry
                .onFailure(throwable -> {
                    <http://logger.info|logger.info>(
                            "Exception when Save Question [" + throwable.getMessage() + "]",
                            throwable
                    );
                })
                .map(gradingRequest -> {
                    return new ResponseEntity<>(
                            new GradingControllerResult(gradingRequest.getId(), createdAt),
                            HttpStatus.OK
                    );
                })
                .orElse(new ResponseEntity<>(HttpStatus.INTERNAL_SERVER_ERROR));

i use javaslang.com that provide

Try

monads for Java 8

Yes I like this syntax too (Rx like) but note that using

onError

onSuccess

basically allows you to not use

Try

at al'

here https://kotlinlang.org/docs/reference/exceptions.html i don’t see any solution for unchecked exception problem.

not like Null handling in kotlin that very-very great.

I thinking to use javaslang with kotlin.

Basically, once you start using Rx, the need for Try evaporates

Yes. but now i heavily using Spring Framework.

i not yet found best practice combining Spring with Rx

About kotlin standard libraries: any plan for implementing two dimensional Array for numerical primitive types? (IntArray2D, LongArray2D, FloatArray2D, DoubleArray2D)

get() and set() operator support multiple indexes, I have just checked

here is a prototype for IntArray2D: https://gist.github.com/beyondeye/0b682229c7759bd82caf

IntArray2d_kt.txt

i thinks it should be a separate library, because 2D arrays are not needed that often

effective (parallel) matrix operations would be nice too

Yes a separate library make sense. Anybody already tried to do it? I mean two dimensional arrays with API in line with stdlib API for arrays?

I am actually don't think that there is any point trying implementing fast matrix operations though. There is Intel MKL and the likes for that, all native code

Don't you think that

val price = "${'$'}9.99"

is an awful way to type

$

character into a string?

We could ease the pain by providing something like

val DS = '$'

in stdlib

so the example above would be

val price = "$DS9.99"

, which is not ideal, but better if everybody know what

DS

is

Is

\$

bad? We can write

val price = "\$9.99"