Fix in move example

Grzegorz Jabłoński
1 parent 5dc62c6a
Showing 1 changed file with 36 additions and 39 deletions
examples05/04-unique_ptr/02-move.cpp
@@ -2,49 +2,46 @@
 #include <memory>
  
 class Example {
-  public:
-    int* val;
-
-    Example(Example&& rhs) : val(rhs.val)
-    {
-        rhs.val = nullptr;
-        std::cout << "Example::Example(Example &&)" << std::endl;
-    }
-
-    Example& operator=(Example&& rhs) // buggy
-    {
-        val = rhs.val;
-        rhs.val = nullptr;
-        std::cout << "Example::operator=(Example &&)" << std::endl;
-        return *this;
-    }
-
-    Example() : val(new int(0))
-    {
-        std::cout << "Example::Example()" << std::endl;
-    }
-
-    Example(int a) : val(new int(a))
-    {
-        std::cout << "Example::Example(" << a << ")" << std::endl;
-    }
-
-    ~Example()
-    {
-        delete val;
-        std::cout << "Example::~Example()" << std::endl;
-    }
+public:
+  int *val;
+
+  Example(Example &&rhs) : val(rhs.val) {
+    rhs.val = nullptr;
+    std::cout << "Example::Example(Example &&)" << std::endl;
+  }
+
+  Example &operator=(Example &&rhs) // buggy
+  {
+    if (&rhs == this)
+      return *this;
+    val = rhs.val;
+    rhs.val = nullptr;
+    std::cout << "Example::operator=(Example &&)" << std::endl;
+    return *this;
+  }
+
+  Example() : val(new int(0)) {
+    std::cout << "Example::Example()" << std::endl;
+  }
+
+  Example(int a) : val(new int(a)) {
+    std::cout << "Example::Example(" << a << ")" << std::endl;
+  }
+
+  ~Example() {
+    delete val;
+    std::cout << "Example::~Example()" << std::endl;
+  }
 };
  
-int main()
-{
-    Example a(3);
+int main() {
+  Example a(3);
  
-    Example b = std::move(a);
+  Example b = std::move(a);
  
-    Example c(Example(4));
+  Example c(Example(4));
  
-    Example d;
+  Example d;
  
-    d = std::move(b);
+  d = std::move(b);
 }