Question

The purpose of my function is to add 5 to an integer as long as that integer is greater than 0 and less than or equal to 7. I try:

val add5Partial : PartialFunction[Int, Int] = {
  case d if (0 < d <= 7) => d + 5;
} 

I get:

<console>:8: error: type mismatch;
 found   : Int(7)
 required: Boolean
         case d if (0 < d <= 7) => d + 5;

Any tips?

Answer 1

Scala do not support such syntax out of the box, so you have to write:

val partial : Int => Int = {
  case d if (d > 0) && (d <= 7) => d + 5;
} 

Alternatively you could do:

val partial : Int => Int = {
  case d if 1 to 7 contains d => d + 5;
}