scala> try ??? catch new { def isDefinedAt(x: Any) = true ; def apply(t: Throwable) = println(t.getMessage) }
warning: there was one feature warning; re-run with -feature for details
an implementation is missing

scala> try ??? catch 22
<console>:8: error: value isDefinedAt is not a member of Int
              try ??? catch 22
                            ^

scala> implicit class depthFinder(i: Int) {
     | def isDefinedAt(x: Any) = true
     | def apply(t: Throwable) = if (t.getStackTrace.length <= i) throw t
     | }
defined class depthFinder

scala> try ??? catch 22

scala> try ??? catch 100
scala.NotImplementedError: an implementation is missing
  at scala.Predef$.$qmark$qmark$qmark(Predef.scala:225)
  at .liftedTree1$1(<console>:10)
  ... 33 elided

scala> val pf: PartialFunction[Any, Int] = { case _ => 42 }
pf: PartialFunction[Any,Int] = <function1>

scala> val pf: PartialFunction[Any, Int] = try { case _ => 42 }
<console>:1: error: '}' expected but 'case' found.
       val pf: PartialFunction[Any, Int] = try { case _ => 42 }
                                                 ^

scala> try ((s: String) => s.length)
<console>:8: warning: A try without a catch or finally is equivalent to putting its body in a block; no exceptions are handled.
              try ((s: String) => s.length)
              ^
res1: String => Int = <function1>