object test { class Foo[a](val arg : a) object Foo { def apply [a](arg : a, right :a) = new Foo[a](arg) def unapply [a](m : Foo[a]) = Some (m.arg) } def matchAndGetArgFromFoo[a]( e:Foo[a]):a = {e match { case Foo(x) => x }} // Try the same thing as above but use function as argument to Bar // constructor type FunIntToA [a] = (Int) => a class Bar[a] (var f: FunIntToA[a]) object Bar { def apply[a](f: FunIntToA[a]) = new Bar[a](f) def unapply[a](m: Bar[a]) = Some (m.f) } def matchAndGetFunFromBar[a](b:Bar[a]) : FunIntToA[a] = { b match { case Bar(x) => x}} }