add smart-point

C++Primer/Template/com.cpp

@@ -9,5 +9,5 @@ int compare(const T &v1, const T &v2) {
 }
 
 int main() {
-
+    cout << compare<int>(1,2);
 }

C++Primer/smart_point/strblob.cpp

@@ -0,0 +1,29 @@
+#include "strblob.h"
+
+// make_shared 在动态内存中分配一个对象并初始化它
+StrBlob::StrBlob(): data(std::make_shared<std::vector<std::string>>()) {};
+
+StrBlob::StrBlob(std::initializer_list<std::string> il): data(std::make_shared<std::vector<std::string>>(il)){};
+
+void StrBlob::check(size_type i, const std::string &msg) const {
+    if (i >= data->size()) {
+        throw std::out_of_range(msg);
+    }
+}
+
+std::string& StrBlob::front() {
+    check(0, "front on empty StrBlob");
+    return data->front();
+}
+
+std::string& StrBlob::back() {
+    check(0, "back on empty StrBlob");
+    return data->back();
+}
+
+void StrBlob::pop_back() {
+    check(0, "pop_back on empty StrBlob");
+    data->pop_back();
+}
+
+

C++Primer/smart_point/strblob.h

@@ -0,0 +1,20 @@
+#include <iostream>
+#include <memory>
+#include <vector>
+#include <string>
+
+class StrBlob {
+public:
+    typedef std::vector<std::string>::size_type size_type;
+    StrBlob();
+    StrBlob(std::initializer_list<std::string> il);
+    size_type size() const {return data->size();}
+    bool empty() const {return data->empty();}
+    void push_back(const std::string &t) {data->push_back(t)};
+    void pop_back();
+    std::string& front();
+    std::string& back();
+private:
+    std::shared_ptr<std::vector<std::string>> data;
+    void check(size_type i, const std::string &msg) const;
+};