Odd behaviour with scala method syntax

Question

Hi chaps, I hit a bit of a quirk of scala's syntax I don't really understand

object Board {
   def getObjectAt(x:Int, y:Int):Placeable = return locations(x)(y)
}

works fine. But

object Board {
   def getObjectAt(x:Int, y:Int):Placeable {
      return locations(x)(y)
   }
}

returns the error

Board.scala:8: error: illegal start of declaration
return locations(x)(y)

I found some stuff that says the second form convinces the scala compiler you're trying to specify an expansion to the return type Placeable. Is there a way I can fix this, or should I just avoid specifying a return type here?

Answer 1

It's just about the function syntax.

If your function has a return value, you'll always define it as an equation (using =), even if a block of computations follows:

object Board {
   def getObjectAt(x:Int, y:Int):Placeable = {
      return locations(x)(y)
   }
}

The notation

def func(...) { ...

is shorthand for return-type Unit, i.e. a function without return value.