While experimenting with some stuff on the REPL, I got to a point where I needed something like this:

scala> class A(x:Int) { println(x); def ==(a:A) : Boolean = { this.x == a.x; } }

Just a simple class with an "==" operator.

Why doesn't it work???

Here's the result:

:10: error: type mismatch;
 found   : A
 required: ?{val x: ?}
Note that implicit conversions are not applicable because they are ambiguous:
 both method any2ArrowAssoc in object Predef of type [A](x: A)ArrowAssoc[A]
 and method any2Ensuring in object Predef of type [A](x: A)Ensuring[A]
 are possible conversion functions from A to ?{val x: ?}
       class A(x:Int) { println(x); def ==(a:A) : Boolean = { this.x == a.x; } }
                                                                        ^

This is scala 2.8 RC1.

Thanks