fix the incorrect order of explanation of the .Error() method (#763)

maps.md

@@ -155,7 +155,8 @@ func TestSearch(t *testing.T) {
 
 The way to handle this scenario in Go is to return a second argument which is an `Error` type.
 
-`Error`s can be converted to a string with the `.Error()` method, which we do when passing it to the assertion. We are also protecting `assertStrings` with `if` to ensure we don't call `.Error()` on `nil`.
+Notice that as we've seen in the [pointers and error section](./pointers-and-errors.md) here in order to asset the error message
+we first check that the error is not `nil` and then use `.Error()` method to get the string which we can then pass to the assertion.
 
 ## Try and run the test
 

pointers-and-errors.md

@@ -455,6 +455,7 @@ Update our helper for a `string` to compare against.
 ```go
 assertError := func(t testing.TB, got error, want string) {
 	t.Helper()
+
 	if got == nil {
 		t.Fatal("didn't get an error but wanted one")
 	}
@@ -465,6 +466,8 @@ assertError := func(t testing.TB, got error, want string) {
 }
 ```
 
+As you can see `Error`s can be converted to a string with the `.Error()` method, which we do in order to compare it with the string we want. We are also making sure that the error is not `nil` to ensure we don't call `.Error()` on `nil`.
+
 And then update the caller
 
 ```go