Merge pull request #1822 from tbodt/patch-1

Explain why nested receivers are dyn-incompatible

Author: ehuss

src/items/traits.md

@@ -173,7 +173,7 @@ trait DynIncompatible {
     fn foo() {}  // ERROR: associated function without Sized
     fn returns(&self) -> Self; // ERROR: Self in return type
     fn typed<T>(&self, x: T) {} // ERROR: has generic type parameters
-    fn nested(self: Rc<Box<Self>>) {} // ERROR: nested receiver not yet supported
+    fn nested(self: Rc<Box<Self>>) {} // ERROR: nested receiver cannot be downcasted
 }
 
 struct S;