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#functional
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# functional
s

Sourabh Rawat

12/16/2021, 7:09 PM
Hi, I have an 
either
block from which I want to return a 
Left
value without any 
bind
calls. For example
Copy code
either<Error, Response> {
 when(foo) {
  1 -> callFunReturningEither().bind()
  else -> Error("foo is in else") <-- How to return this Left value?
 }
}
I have tried 
Error("foo is in else").left().bind()
but it gives 
Returning type parameter has been inferred to Nothing implicitly. Please specify type arguments explicitly to hide this warning. Nothing can produce an exception at runtime.
which I think is expected.
r

raulraja

12/16/2021, 7:35 PM
Hi @Sourabh Rawat, not sure if there is additional code in the mix but if you are not using 
bind
there is no point of wrapping in an either block. It would be in this case just:
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val result: Either<Error, Response> = 
  when(foo) {
    1 -> callFunReturningEither()
    else -> Either.Left(Error("foo is in else"))
   }
s

simon.vergauwen

12/16/2021, 8:20 PM
Copy code
when(foo) {
  1 -> callFunReturningEither()
  else -> Error("foo is in else").left()
 }
That is not an error the compiler gave you there though, and the code will work as you expect when doing.
Copy code
either<Error, Response> {
 when(foo) {
  1 -> callFunReturningEither()
  else -> Error("foo is in else").left().bind()
 }
}
p

pakoito

12/16/2021, 8:53 PM
you have to 
bind
the return of 
1 ->
I believe
s

Sourabh Rawat

12/17/2021, 4:31 AM
Oh yea sorry, there was a typo in the original code. It does have 
bind
call in 
1 ->
clause
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