test a reference as a lvalue

.gitignore

@@ -15,3 +15,4 @@ object-lifetime
 shared_ptr
 casts
 classes
+lvalues

CMakeLists.txt

@@ -15,3 +15,4 @@ add_executable(object-lifetime object-lifetime.cpp)
 add_executable(shared_ptr shared_ptr.cpp)
 add_executable(casts casts.cpp)
 add_executable(classes classes.cpp)
+add_executable(lvalues lvalues.cpp)

lvalues.cpp

@@ -0,0 +1,31 @@
+#include <cassert>
+
+int test = 12;
+
+int fnord_(const int i) {
+  test += i;
+  return test;
+}
+
+int& fnord(const int i) {
+  test += i;
+  return test;
+}
+
+int main() {
+  test = 13;
+
+  fnord_(5);
+  assert(test == 18);
+
+  // LOLNOPE:
+  // fnord_(5)++;
+
+  test = 13;
+
+  fnord(5);
+  assert(test == 18);
+
+  fnord(5)++;
+  assert(test == 24);
+}