Hi, First of all many thanks to Arrow team for offering such a great FP companion library to kotlin...

# arrow

[jtonic]

Hi,

First of all many thanks to Arrow team for offering such a great FP companion library to kotlin community.
I really like the new version 1.2 and looking forward to future version, 2.0.
On the other hand I’ve started to read the great book about FP - Functional Programming Ideas for the Curious Kotliner.
I do really like the way FP is exposed to regular kotliners by @Alejandro Serrano Mena, and it is an amazing learning material, alongside the arrow-kt.io online reference documentation.
Regarding the book (which is currently in beta) I do kindly have a question about : Are the Arrow APIs used in the book's examples going to be updated to arrow 1.2? For instance in the chapter about Either, and validation accumulation the Validated API and Co. are used.

Thanks in advance for your thoughts.

[Alejandro Serrano Mena]

the book is already updated for Arrow 1.2/2.0; in fact it defines Validation<E, A> as Either<List<E>, A>, which is almost the same encoding as current Arrow

(the reason it’s not the same is because Arrow uses Either<NonEmptyList<E>, A>, but I didn’t want to introduce extra difficulties at that point)