object TestIt extends App { 

 { // if you remove this bracket block, the compiler does not complain
   def memoize1[A, B](f: A => B): Function1[A, B] = new Function1[A, B] {
     val results = collection.mutable.Map.empty[A, B]
     def apply(in: A) = results.getOrElseUpdate(in, f(in))
   }

   val maxLatency1: Function1[(Int, Int), Int] = memoize1 { t: (Int, Int) =>
     val (s, d) = t
     if (s == d) 0
     else {
       maxLatency1((1, 2))
     }
   }
 } // end of block

}