Add Universal Function Call Syntax example

Author: GuillaumeGomez

src/librustc_typeck/diagnostics.rs

@@ -212,8 +212,8 @@ http://doc.rust-lang.org/reference.html#trait-objects
 "##,
 
 E0034: r##"
-The compiler doesn't know what method to call because more than one does
-have the same prototype. Example:
+The compiler doesn't know what method to call because more than one method
+has the same prototype. Example:
 
 ```
 struct Test;
@@ -230,7 +230,7 @@ impl Trait1 for Test { fn foo() {} }
 impl Trait2 for Test { fn foo() {} }
 
 fn main() {
-    Test::foo() // error, what foo() to call?
+    Test::foo() // error, which foo() to call?
 }
 ```
 
@@ -250,6 +250,28 @@ fn main() {
     Test::foo() // and now that's good!
 }
 ```
+
+However, a better solution would be using fully explicit naming of type and
+trait:
+
+```
+struct Test;
+
+trait Trait1 {
+    fn foo();
+}
+
+trait Trait2 {
+    fn foo();
+}
+
+impl Trait1 for Test { fn foo() {} }
+impl Trait2 for Test { fn foo() {} }
+
+fn main() {
+    <Test as Trait1>::foo()
+}
+```
 "##,
 
 E0035: r##"