Sammy + wildcards + type inference = :(

Hello,

Is there any chance this will work?

$ scala -Xexperimental
Welcome to Scala version 2.11.6 (Java HotSpot(TM) 64-Bit Server VM, Java 1.8
.0_40).
Type in expressions to have them evaluated.
Type :help for more information.

scala> new java.util.ArrayList[String]().stream.map(_.toInt)
<console>:8: error: no type parameters for method map: (x$1: java.util.
function.Function[_ >: String, _ <: R])java.util.stream.Stream[R] exist so 
that it can be applied to arguments (java.util.function.Function[String,Int] 
with Serializable)
 --- because ---
argument expression's type is not compatible with formal parameter type;
 found   : java.util.function.Function[String,Int] with Serializable
 required: java.util.function.Function[_ >: String, _ <: ?R]
Note: String <: Any (and java.util.function.Function[String,Int] with 
Serializable <: java.util.function.Function[String,Int]), but Java-defined 
trait Function is invariant in type T.
You may wish to investigate a wildcard type such as `_ <: Any`. (SLS 3.2.10)
              new java.util.ArrayList[String]().stream.map(_.toInt)
                                                       ^
<console>:8: error: type mismatch;
 found   : java.util.function.Function[String,Int] with Serializable
 required: java.util.function.Function[_ >: String, _ <: R]
              new java.util.ArrayList[String]().stream.map(_.toInt)

It would be a very disappointing limitation if it won't - it would negate 
the most important promise of Sammy, which is good Java interop.

Thanks,
Roman

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