This demonstrates some of the ways to combine scalaz6 Validaitons. It is the result of answers to question http://stackoverflow.com/questions/13961940/chaining-scalaz-validation-functions-function1a-validatione-b. See answers for more, including combining functions using Kliesi in scalaz6 and scalaz7.

gistfile1.txt

def allDigits: (String) => ValidationNEL[String, String]
def maxSizeOfTen: (String) => ValidationNEL[String, String] 
def toInt: (String) => ValidationNEL[String, Int]

val validInt: String => ValidationNEL[String, Int] = s =>
  for {
    validStr <- (allDigits(s) |@| maxSizeOfTen(s))((_,x) => x)
    i <- toInt(validStr)
  } yield(i)

val validInt: String => ValidationNEL[String, Int] = s =>
  for {
    _ <- (allDigits(s) <|*|> maxSizeOfTen(s))
    i <- toInt(s)
} yield(i)

//or

val validInt: String => ValidationNEL[String, Int] = s =>
  for {
    validStr <- (allDigits(s) *> maxSizeOfTen(s))
    i <- toInt(validStr)
} yield(i)

//or

val validInt: String => ValidationNEL[String, Int] = s =>
  for {
    validStr <- (allDigits(s) <* maxSizeOfTen(s))
    i <- toInt(validStr)
} yield(i)

//or

val validInt: String => ValidationNEL[String, Int] = s =>
  (allDigits(s) *> maxSizeOfTen(s)) flatMap toInt