Using Either to process failures in Scala code

Question

Option monad is a great expressive way to deal with something-or-nothing things in Scala. But what if one needs to log a message when \"nothing\" occurs? Accord

Answer 1

Cats has a nice way to create an Either from exception-throwing code:

val either: Either[NumberFormatException, Int] =
  Either.catchOnly[NumberFormatException]("abc".toInt)
// either: Either[NumberFormatException,Int] = Left(java.lang.NumberFormatException: For input string: "abc")

in https://typelevel.org/cats/datatypes/either.html#working-with-exception-y-code