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def ints(n: Int): Stream[Int] = Stream.cons(n, ints(n+1)) 
def primes(nums: Stream[Int]): Stream[Int] = Stream.cons(nums.head, 
primes 
((nums tail) filter (x => x % nums.head != 0)) ) 
val allPrimes = primes(ints(2)) 
def goldbach(i: Int) = { 
  val primes = allPrimes.takeWhile(_ < i).toSet 
  val intersection = primes & primes.map(i - _) 
  if (intersection.isEmpty) 
    throw new RuntimeException("I found a goldbach counter-example: " + 
i) 
  (intersection.head, i - intersection.head) 

Main.scala:1: error: expected class or object definition
def ints(n: Int): Stream[Int] = Stream.cons(n, ints(n+1)) 
^
Main.scala:2: error: expected class or object definition
def primes(nums: Stream[Int]): Stream[Int] = Stream.cons(nums.head, 
^
Main.scala:5: error: expected class or object definition
val allPrimes = primes(ints(2)) 
^
Main.scala:6: error: expected class or object definition
def goldbach(i: Int) = { 
^
Main.scala:11: error: Missing closing brace `}' assumed here
i) 
^
Main.scala:12: error: expected class or object definition
  (intersection.head, i - intersection.head) 
  ^
6 errors found

Standard output is empty