@pakoito great minds

fun <A, B>Either<A, B>.filterOrHandle(p: (B) -> Boolean, f: (B) -> A): Either<A, B> {
    
}

I was two seconds behind you

hahahah

I started with the original implementation and modified, got me the extra frames advantage 😛

I should have the source code open all the time

Want to make a contribution to arrow. Have cloned, but getting errors building on Windows. Using ./gradlew build and getting this. Seems like an issue with Detekt. Running JDK8 at the moment. Anyone else experienced this?

Task :detekt FAILED

Was passed main parameter 'C:\Users\mikez\dev\arrow/reports/report.detekt' but no main parameter was defined in your arg class Usage: detekt [options] Options: --baseline, -b If a baseline xml file is passed in, only new code smells not in the baseline are printed in the console. --config, -c Path to the config file (path/to/config.yml).

Is there a class

Undefined

in library? Something like https://wiki.haskell.org/Undefined or like

undefined

from JavaScript I need it to implement this https://medium.com/workflowgen/graphql-mutations-partial-updates-implementation-bff586bda989

@rrader I believe in Kotlin that is

TODO()

Returns Nothing which is the Kotlin bottom type

Can be placed anywhere and it will compile and blow up at runtime if someone crosses its path

you’re looking for a simple nullable type, don’t overthink it

nullable or Option

I saw the kotlin gradle dsl was upgrade as stable

1.0.0

when kotlin

1.3.0

was launched. It's a good idea to use it/migrate instead of standard gradle?

If I was going to model the behaviour of an event sourced aggregate should I use the

StateT

for that?

Basically the aggregate needs to take a command/event(s) and return back the new aggregate and an optional list of events.

It sounds like a job for

State

or StateT`.

Hi guys. Is there any reason why something like

Try { "$%" }.map { it.toInt() }

throws an exception rather than returning a

Failure

?

.map must not try/catch, I think it's only the constructor that does

if .map performed try/catch, it wouldn't conform to the functor laws, so it wouldn't make sense

If you want that behavior you should use

flatMap

instead. Where the throwing operation is actually wrapped in

Try

Not sure what your use case is tho because here you’re better of with just

Try { "$%".toInt() }

Hmm, I can appreciate that. But having used Vavr in Java or

Try

in Scala I got caught out by this behaviour

It was obviously just an example to demonstrate the behaviour. Of course you can just do

Try { "$%".toInt() }

🙂

Hehe

Not sure about Scala’s std

Try

or

Vavr

. @raulraja could probably give you a better explanation related to that.

IIRC Cats overrides that behavior but I am not sure.

As in that

Try.map { f() }

catches but

Functor[Try].map(try)(a => f(a))

doesn’t

scala's stdlib doesn't really pay attention to laws, right?

No it doesn’t

hence scalaz or cats