I believe this one is for the debugger, I've been ...

# arrow

[pakoito]

I believe this one is for the debugger, I've been able to repro but cannot dig into what happens when !put("A", 1) is called. We know it never reaches the interpreter.

[PhBastiani]

val test = KVStoreA.put("aa", 1)
        .flatMap {KVStoreA.get<Int>("aa")}
        .run(interpreterState, State().monad()).fix()
        .runS (emptyMap<String, Int>())
    println("test -> $test")

test -> {aa=1}
So, flatMap works as expected...

[PhBastiani]

Note: my implementation of `KVStoreA.Get<*>`is erroneous... runA throws a class cast exception ! but it's an other problem...

[pakoito]

which version are you in?

[pakoito]

0.9 or 0.10-SNAP?

[PhBastiani]

0.10

[pakoito]

weird

[pakoito]

can you please check on a debugger where it

[pakoito]

it's stuck?

[pakoito]

there needs to be some sync await, or somewhere where the thread is stuck waiting

[pakoito]

not waiting but...not executing

[PhBastiani]

The flatMapped version works with an explicit type:
is KVStoreA.Get<*> -> State().inspect { it : Map<String, Any?> -> Option.fromNullable(it[op.key]) }

val test =KVStoreA.put("aa", 1) 
        .flatMap {KVStoreA.get<Int>("aa")}
        .run(interpreterState, State().monad()).fix()
        .runA(emptyMap<String, Int>())
    println("test -> $test")

gives test -> Some(1)

=> Each case of the natural transformation should be typed !
The behavior of the compilo is strange 🙃

[PhBastiani]

Tomorrow, i will check the type of val a = !put("A", 1) … i've no compilator on hand

[pakoito]

👍🏼

[pakoito]

I did it on try.arrow, they’re Unit and Option<Int>

[pakoito]

it has to be something on Free

[PhBastiani]

Me too. We get the type of Put transformation (i.e. the first/previous transformation).
But, that does not explain why the program is not executed...

[PhBastiani]

Paco, I fixed my GIST 😃
In fact, a fix() was missing before the call of run(initialtstate). Thx for your help.

[PhBastiani]

I saw too late that my run was not applied on the right object.
I will dig to understand the non execution of the program without fix

[pakoito]

it was using the scope run function from kotlin

[pakoito]

not the run member function that you expected

[pakoito]

how did you find ot?

[PhBastiani]

I ended up seeing the braces...

[PhBastiani]

Ok, now to continue my learning of Arrow, I will create instances of Inject and try to compose DSL ...

[pakoito]

We should rename that method TBH

[pakoito]

I’ll do it now

[PhBastiani]

In any case, I should have noticed that my program did not return a Tuple2