Better suggestions for error handling

exercises/practice/hamming/.docs/instructions.append.md

@@ -1,6 +1,14 @@
 # Instructions append
 
+With this exercise, you are introduced to the use of
+[multiple results](multiple_returns) feature and here there
+is an example with [errors](errors)
+
+    func Foo(a, b string) (string, error) {
+        return "", errors.New("An error occurred!")
+    }
+
 You may be wondering about the `cases_test.go` file. We explain it in the
 [leap exercise][leap-exercise-readme].
 
-[leap-exercise-readme]: https://github.com/exercism/go/blob/master/exercises/leap/README.md 
+[leap-exercise-readme]: https://github.com/exercism/go/blob/master/exercises/leap/README.md

exercises/practice/hamming/.docs/instructions.md

@@ -20,5 +20,4 @@ The Hamming Distance is useful for lots of things in science, not just biology,
 
 The Hamming distance is only defined for sequences of equal length, so
 an attempt to calculate it between sequences of different lengths should
-not work. The general handling of this situation (e.g., raising an
-exception vs returning a special value) may differ between languages.
+not work.