From Programming Scala book I read that in following code configFilePath constant will be type of Unit:
scala> val configFilePat
if (cond) { expr } returns common base type of Unit and type of expr, just like if (cond) { expr } else { () }.
It is AnyVal for Int, Char and so on, Unit for Unit and Any for AnyRef:
scala> if ( false ) 1
res0: AnyVal = ()
scala> val r = if ( false ) { () }
r: Unit = ()
scala> if ( false ) ""
res1: Any = ()