add Chapter06

Chapter06/rvalue_refs.cpp

@@ -0,0 +1,27 @@
+#include <string> 
+#include <vector>  
+#include <cstdio> 
+
+int main() 
+{ 
+
+    std::string str = "Hello world, this is move semantics demo!!!"; 
+    printf("str.data address is %p\r\n", (void*)str.data()); 
+
+    std::vector<std::string> v; 
+
+    v.push_back(str); 
+    printf("str after copy is <%s>\r\n", str.data()); 
+
+    v.push_back(std::move(str)); 
+    //v.push_back(static_cast<std::string&&>(str)); 
+
+    printf("str after move is <%s>\r\n", str.data()); 
+
+    for(const auto & s:v) { 
+        printf("s is <%s>\r\n", s.data()); 
+        printf("s.data address is %p\r\n", (void*)s.data()); 
+    } 
+
+    return 0; 
+}