fix(A8-4-9): Split A8-4-8 and A8-4-9

src/A8-4-8.md

@@ -29,35 +29,35 @@ struct B
 
 struct BB
 {
-B GetB() const& { return obj; }
-B&& GetB() && { return std::move(obj); }
+    B GetB() const& { return obj; }
+    B&& GetB() && { return std::move(obj); }
 
-B obj;
+    B obj;
 
 };
 
 // Non-compliant: returns a dangling reference
 BB&& MakeBb1()
 {
-return std::move(BB());
+    return std::move(BB());
 }
 
 // Compliant: uses compiler copy-ellision
 BB MakeBb2()
 {
-return BB();
+    return BB();
 
 }
 
 int main()
 {
-BB x = MakeBb2();
+    BB x = MakeBb2();
 
-auto cpd = x.GetB();
-// copied value
-auto mvd = MakeBb2().GetB(); // moved value
+    auto cpd = x.GetB();
+    // copied value
+    auto mvd = MakeBb2().GetB(); // moved value
 
-return 0;
+    return 0;
 
 }
 
@@ -67,51 +67,3 @@ return 0;
 
 C++ Core Guidelines [11]: F.20: For ”out” output values, prefer return values to
 output parameters.
-Rule A8-4-9 (required, design, automated) ”in-out”
-parameters declared as T & shall be modified.
-
-## Rationale
-
-An ”in-out” parameter is declared with a type of reference to non-const. This means
-that a fully constructed object is passed into the function that can be read as well as
-modified.
-Note: Completely replacing the passed in object without reading any data from it
-would make it an ”out” parameter instead and is not considered compliant with this
-rule, also see rule: A8-4-8
-
-## Example
-
-```cpp
-// $Id: A8-4-9.cpp 306178 2018-02-01 15:52:25Z christof.meerwald $
-
-#include <cstdint>
-#include <numeric>
-#include <string>
-#include <vector>
-
-// Non-Compliant: does not modify the "in-out" parameter
-int32_t Sum(std::vector<int32_t> &v)
-{
-return std::accumulate(v.begin(), v.end(), 0);
-}
-
-// Compliant: Modifying "in-out" parameter
-void AppendNewline(std::string &s)
-{
-s += ’\n’;
-}
-
-// Non-Compliant: Replacing parameter value
-void GetFileExtension(std::string &ext)
-{
-ext = ".cpp";
-}
-
-```
-
-## See also
-
-C++ Core Guidelines [11]: F.17: For ”in-out” parameters, pass by reference to
-non-const
-JSF December 2005 [8]: AV Rule 117.2: An object should be passed as T& if
-the function may change the value of the object.

src/A8-4-9.md

@@ -0,0 +1,49 @@
+> **Rule A8-4-9 (required, design, automated)**
+>
+> ”in-out” parameters declared as T & shall be modified.
+
+## Rationale
+
+An ”in-out” parameter is declared with a type of reference to non-const. This means
+that a fully constructed object is passed into the function that can be read as well as
+modified.
+Note: Completely replacing the passed in object without reading any data from it
+would make it an ”out” parameter instead and is not considered compliant with this
+rule, also see rule: A8-4-8
+
+## Example
+
+```cpp
+// $Id: A8-4-9.cpp 306178 2018-02-01 15:52:25Z christof.meerwald $
+
+#include <cstdint>
+#include <numeric>
+#include <string>
+#include <vector>
+
+// Non-Compliant: does not modify the "in-out" parameter
+int32_t Sum(std::vector<int32_t> &v)
+{
+    return std::accumulate(v.begin(), v.end(), 0);
+}
+
+// Compliant: Modifying "in-out" parameter
+void AppendNewline(std::string &s)
+{
+    s += ’\n’;
+}
+
+// Non-Compliant: Replacing parameter value
+void GetFileExtension(std::string &ext)
+{
+    ext = ".cpp";
+}
+
+```
+
+## See also
+
+C++ Core Guidelines [11]: F.17: For ”in-out” parameters, pass by reference to
+non-const
+JSF December 2005 [8]: AV Rule 117.2: An object should be passed as T& if
+the function may change the value of the object.

src/SUMMARY.md

@@ -192,6 +192,7 @@
   - [A8-4-6](./A8-4-6.md)
   - [A8-4-7](./A8-4-7.md)
   - [A8-4-8](./A8-4-8.md)
+  - [A8-4-9](./A8-4-9.md)
   - [A8-4-10](./A8-4-10.md)
   - [A8-4-11](./A8-4-11.md)
   - [A8-4-12](./A8-4-12.md)