update

README.md

@@ -139,6 +139,9 @@ for(decl:col) {
   - [引用折叠](./modern_C++_30/reference/collapses.cpp)
   - [完美转发](./modern_C++_30/reference/forward.cpp)
   - [不要返回本地变量的引用](./modern_C++_30/reference/don'treturnReference.cpp)
+- [容器1](./modern_C++_30/container1)
+- [容器2](./modern_C++_30/container2)
+- [异常](./modern_C++_30/exception)
 
 ### 4.拓展部分
 

modern_C++_30/CMakeLists.txt

@@ -18,3 +18,12 @@ add_executable(forward reference/forward.cpp)
 add_executable(collapses reference/collapses.cpp)
 add_executable(lifetime reference/lifetime.cpp)
 add_executable(dontreturnReference reference/don'treturnReference.cpp)
+
+add_executable(container container1/container.cpp)
+add_executable(cont container2/hash.cpp)
+add_executable(vector_l container1/vector_l.cpp)
+add_executable(priority_queue container2/priority_queue.cpp)
+add_executable(relacontainer container2/relacontainer.cpp)
+add_executable(unorder container2/unorder.cpp)
+add_executable(array container2/array.cpp)
+add_executable(exception exception/exception.cpp)

modern_C++_30/CMakeLists.txt~

@@ -12,3 +12,9 @@ add_executable(auto_scope smart_ptr/auto_scope.cpp)
 add_executable(unique_ptr smart_ptr/unique_ptr.cpp)
 add_executable(unique_ptr_U smart_ptr/unique_ptr_U.cpp)
 add_executable(shared_ptr smart_ptr/shared_ptr.cpp)
+
+add_executable(reference reference/reference.cpp)
+add_executable(forward reference/forward.cpp)
+add_executable(collapses reference/collapses.cpp)
+add_executable(lifetime reference/lifetime.cpp)
+add_executable(dontreturnReference reference/don'treturnReference.cpp)

modern_C++_30/container1/container.cpp

@@ -0,0 +1,21 @@
+//
+// Created by light on 19-12-16.
+//
+
+#include <iostream>
+#include <map>
+#include <vector>
+#include "output_container.h"
+
+using namespace std;
+
+int main()
+{
+    map<int, int> mp{
+            {1, 1}, {2, 4}, {3, 9}};
+    cout << mp << endl;
+    vector<vector<int>> vv{
+            {1, 1}, {2, 4}, {3, 9}};
+    cout << vv << endl;
+
+}

modern_C++_30/container1/output_container.h

@@ -0,0 +1,148 @@
+/*
+ * Written by Wu Yongwei <wuyongwei AT gmail DOT com>.
+ *
+ * Using this file requires a C++17-compliant compiler.
+ *
+ * This is free and unencumbered software released into the public domain.
+ *
+ * Anyone is free to copy, modify, publish, use, compile, sell, or
+ * distribute this software, either in source code form or as a compiled
+ * binary, for any purpose, commercial or non-commercial, and by any
+ * means.
+ *
+ * In jurisdictions that recognize copyright laws, the author or authors
+ * of this software dedicate any and all copyright interest in the
+ * software to the public domain. We make this dedication for the benefit
+ * of the public at large and to the detriment of our heirs and
+ * successors. We intend this dedication to be an overt act of
+ * relinquishment in perpetuity of all present and future rights to this
+ * software under copyright law.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * For more information, please refer to <http://unlicense.org>
+ *
+ */
+
+#ifndef OUTPUT_CONTAINER_H
+#define OUTPUT_CONTAINER_H
+
+#include <ostream>      // std::ostream
+#include <type_traits>  // std::false_type/true_type/decay_t/is_same_v
+#include <utility>      // std::declval/pair
+
+// Type trait to detect std::pair
+template <typename T>
+struct is_pair : std::false_type {};
+template <typename T, typename U>
+struct is_pair<std::pair<T, U>> : std::true_type {};
+template <typename T>
+inline constexpr bool is_pair_v = is_pair<T>::value;
+
+// Type trait to detect whether an output function already exists
+template <typename T>
+struct has_output_function {
+    template <class U>
+    static auto output(U* ptr)
+    -> decltype(std::declval<std::ostream&>() << *ptr,
+            std::true_type());
+    template <class U>
+    static std::false_type output(...);
+    static constexpr bool value =
+            decltype(output<T>(nullptr))::value;
+};
+template <typename T>
+inline constexpr bool has_output_function_v =
+        has_output_function<T>::value;
+/* NB: Visual Studio 2017 (or below) may have problems with
+ *     has_output_function_v<T>: you should then use
+ *     has_output_function<T>::value instead, or upgrade to
+ *     Visual Studio 2019. */
+
+// Output function for std::pair
+template <typename T, typename U>
+std::ostream& operator<<(std::ostream& os, const std::pair<T, U>& pr);
+
+// Element output function for containers that define a key_type and
+// have its value type as std::pair
+template <typename T, typename Cont>
+auto output_element(std::ostream& os, const T& element,
+                    const Cont&, const std::true_type)
+-> decltype(std::declval<typename Cont::key_type>(), os);
+// Element output function for other containers
+template <typename T, typename Cont>
+auto output_element(std::ostream& os, const T& element,
+                    const Cont&, ...)
+-> decltype(os);
+
+// Main output function, enabled only if no output function already exists
+template <typename T,
+        typename = std::enable_if_t<!has_output_function_v<T>>>
+auto operator<<(std::ostream& os, const T& container)
+-> decltype(container.begin(), container.end(), os)
+{
+    using std::decay_t;
+    using std::is_same_v;
+
+    using element_type = decay_t<decltype(*container.begin())>;
+    constexpr bool is_char_v = is_same_v<element_type, char>;
+    if constexpr (!is_char_v) {
+        os << "{ ";
+    }
+    if (!container.empty()) {
+        auto end = container.end();
+        bool on_first_element = true;
+        for (auto it = container.begin(); it != end; ++it) {
+            if constexpr (is_char_v) {
+                if (*it == '\0') {
+                    break;
+                }
+            }
+            if constexpr (!is_char_v) {
+                if (!on_first_element) {
+                    os << ", ";
+                } else {
+                    on_first_element = false;
+                }
+            }
+            output_element(os, *it, container, is_pair<element_type>());
+        }
+    }
+    if constexpr (!is_char_v) {
+        os << " }";
+    }
+    return os;
+}
+
+template <typename T, typename Cont>
+auto output_element(std::ostream& os, const T& element,
+                    const Cont&, const std::true_type)
+-> decltype(std::declval<typename Cont::key_type>(), os)
+{
+    os << element.first << " => " << element.second;
+    return os;
+}
+
+template <typename T, typename Cont>
+auto output_element(std::ostream& os, const T& element,
+                    const Cont&, ...)
+-> decltype(os)
+{
+    os << element;
+    return os;
+}
+
+template <typename T, typename U>
+std::ostream& operator<<(std::ostream& os, const std::pair<T, U>& pr)
+{
+    os << '(' << pr.first << ", " << pr.second << ')';
+    return os;
+}
+
+#endif // OUTPUT_CONTAINER_H

modern_C++_30/container1/vector_l.cpp

@@ -0,0 +1,64 @@
+//
+// Created by light on 19-12-16.
+//
+#include <vector>
+#include <iostream>
+#include <queue>
+using namespace std;
+
+class Obj1 {
+public:
+    Obj1()
+    {
+        cout << "Obj1()\n";
+    }
+    Obj1(const Obj1&)
+    {
+        cout << "Obj1(const Obj1&)\n";
+    }
+    Obj1(Obj1&&)
+    {
+        cout << "Obj1(Obj1&&)\n";
+    }
+};
+
+class Obj2 {
+public:
+    Obj2()
+    {
+        cout << "Obj2()\n";
+    }
+    Obj2(const Obj2&)
+    {
+        cout << "Obj2(const Obj2&)\n";
+    }
+    Obj2(Obj2&&) noexcept
+    {
+        cout << "Obj2(Obj2&&)\n";
+    }
+};
+
+int main()
+{
+    vector<int> v;
+
+    int nums = 20;
+    for (int i = 0; i < nums; ++i) {
+        v.push_back(i + 1);
+        cout << "v_size: " << v.size() << "\t v_capacity: " << v.capacity() << endl;
+    }
+    // 头两个在已有空间上成功构造。第三个时发现空间不足，系统会请求更大的空间，大小由实现决定（比如两倍）。
+    // 有了足够的空间后，就会在新空间的第三个的位置构造（第三个obj1），成功之后再把头两个拷贝或移动过来。
+    vector<Obj1> v1;
+//    v1.reserve(2);
+    v1.emplace_back();
+    v1.emplace_back();
+    v1.emplace_back();
+    v1.emplace_back();
+
+    vector<Obj2> v2;
+    v2.reserve(2);
+    v2.emplace_back();
+    v2.emplace_back();
+    v2.emplace_back();
+}

modern_C++_30/container2/array.cpp

@@ -0,0 +1,53 @@
+//
+// Created by light on 19-12-16.
+//
+
+#include <iostream>
+#include <map>  // std::map
+#include "../container1/output_container.h"
+
+using namespace std;
+#define ARRAY_LEN(a) \
+  (sizeof(a) / sizeof((a)[0]))
+
+
+void test(int a[8]) {
+    cout << ARRAY_LEN(a) << endl;
+}
+
+
+void test1(int arr[]) {
+    //      不能编译
+//     std::cout << std::size(arr)
+//               << std::endl;
+}
+
+
+typedef char mykey_t[8];
+typedef std::array<char, 8> mykey_t1;
+
+int main() {
+    int a[8];
+    test(a);
+
+
+    // C++17 直接提供了一个 size 方法，可以用于提供数组长度，
+    int arr[] = {1, 2, 3, 4, 5};
+    std::cout << "The array length is "
+              << std::size(arr)
+              << std::endl;
+    // 并且在数组退化成指针的情况下会直接失败
+    test1(arr);
+
+
+    std::map<mykey_t, int> mp;
+    mykey_t mykey{"hello"};
+//    mp[mykey] = 5;
+    //  轰，大段的编译错误
+
+
+    std::map<mykey_t1, int> mp1;
+    mykey_t1 mykey1{"hello"};
+    mp1[mykey1] = 5;    // ok
+    cout << mp1 << endl;
+}

modern_C++_30/container2/hash.cpp

@@ -0,0 +1,46 @@
+//
+// Created by light on 19-12-16.
+//
+
+
+#include <algorithm>   // std::sort
+#include <functional>  // std::less/greater/hash
+#include <iostream>    // std::cout/endl
+#include <string>      // std::string
+#include <vector>      // std::vector
+#include "../container1/output_container.h"
+
+using namespace std;
+
+int main()
+{
+    //  初始数组
+    vector<int> v{13, 6, 4, 11, 29};
+    cout << v << endl;
+
+    //  从小到大排序
+    sort(v.begin(), v.end());
+    cout << v << endl;
+
+    //  从大到小排序
+    sort(v.begin(), v.end(),
+         greater<int>());
+    cout << v << endl;
+
+    cout << hex;
+
+    auto hp = hash<int*>();
+    cout << "hash(nullptr)  = "
+         << hp(nullptr) << endl;
+    cout << "hash(v.data()) = "
+         << hp(v.data()) << endl;
+    cout << "v.data()       = "
+         << static_cast<void*>(v.data())
+         << endl;
+
+    auto hs = hash<string>();
+    cout << "hash(\"hello\")  = "
+         << hs(string("hello")) << endl;
+    cout << "hash(\"hellp\")  = "
+         << hs(string("hellp")) << endl;
+}

modern_C++_30/container2/priority_queue.cpp

@@ -0,0 +1,30 @@
+//
+// Created by light on 19-12-16.
+//
+
+
+#include <functional>  // std::greater
+#include <iostream>    // std::cout/endl
+#include <memory>      // std::pair
+#include <queue>       // std::priority_queue
+#include <vector>      // std::vector
+#include "../container1/output_container.h"
+
+using namespace std;
+
+int main()
+{
+    priority_queue<
+            pair<int, int>,
+            vector<pair<int, int>>,
+            greater<pair<int, int>>>
+            q;
+    q.push({1, 1});
+    q.push({2, 2});
+    q.push({0, 3});
+    q.push({9, 4});
+    while (!q.empty()) {
+        cout << q.top() << endl;
+        q.pop();
+    }
+}

modern_C++_30/container2/relacontainer.cpp

@@ -0,0 +1,73 @@
+//
+// Created by light on 19-12-16.
+//
+
+#include <iostream>
+#include <functional>
+#include <map>
+#include <set>
+#include <string>
+#include "../container1/output_container.h"
+#include <tuple>
+
+using namespace std;
+
+int main() {
+    set<int> s{1, 1, 1, 2, 3, 4};
+    cout << s << endl;
+
+    multiset<int, greater<int>> ms{1, 1, 1, 2, 3, 4};
+    cout << ms << endl;
+
+
+    map<string, int> mp{
+            {"one",   1},
+            {"two",   2},
+            {"three", 3},
+            {"four",  4}
+    };
+
+    cout << mp << endl;
+
+
+    mp.insert({"four", 4});
+    cout << mp << endl;
+
+    cout << (mp.find("four") == mp.end()) << endl;
+
+    cout << (mp.find("five") == mp.end()) << endl;
+
+    mp["five"] = 5;
+
+    cout << mp << endl;
+
+
+    multimap<string, int> mmp{
+            {"one",   1},
+            {"two",   2},
+            {"three", 3},
+            {"four",  4}
+    };
+
+    cout << mmp << endl;
+
+    mmp.insert({"four", -4});
+
+    cout << mmp << endl;
+
+    cout << (mp.find("four")->second) << endl;
+    cout << (mp.lower_bound("four")->second) << endl;
+
+    cout << (mp.upper_bound("four")->second) << endl;
+    cout << ((--mp.upper_bound("four"))->second) << endl;
+
+    multimap<string, int>::iterator
+            lower, upper;
+    std::tie(lower, upper) =
+            mmp.equal_range("four");
+    cout << (lower != upper) << endl;   // 检测区间非空
+
+    cout << lower->second << endl;
+    cout << (--upper)->second << endl;
+
+}

modern_C++_30/container2/unorder.cpp

@@ -0,0 +1,41 @@
+//
+// Created by light on 19-12-16.
+//
+
+
+#include <complex>        // std::complex
+#include <iostream>       // std::cout/endl
+#include <unordered_map>  // std::unordered_map
+#include <unordered_set>  // std::unordered_set
+#include "../container1/output_container.h"
+
+using namespace std;
+
+namespace std {
+
+    template <typename T>
+    struct hash<complex<T>> {
+        size_t
+        operator()(const complex<T>& v) const
+        noexcept
+        {
+            hash<T> h;
+            return h(v.real()) + h(v.imag());
+        }
+    };
+
+}  // namespace std
+
+int main()
+{
+    unordered_set<int> s{
+            1, 1, 2, 3, 5, 8, 13, 21
+    };
+    cout << s << endl;
+
+    unordered_map<complex<double>,
+            double>
+            umc{{{1.0, 1.0}, 1.4142},
+                {{3.0, 4.0}, 5.0}};
+    cout << umc << endl;
+}

modern_C++_30/exception/exception.cpp

@@ -0,0 +1,21 @@
+//
+// Created by light on 19-12-17.
+//
+
+#include <vector>
+#include <iostream>
+
+// “首先是内存分配。如果 new 出错，按照 C++ 的规则，一般会得到异常 bad_alloc，对象的构造也就失败了。
+// 这种情况下，在 catch 捕捉到这个异常之前，所有的栈上对象会全部被析构，资源全部被自动清理。”
+// 之所以是栈上对象会全被被析构原因是堆上的东西都是由栈上的变量所引用的，栈上对象析构的过程，
+// 堆上相应的资源自然就被释放了。而且被释放的对象的范围还被栈帧限定了。
+
+
+// -fexceptions（缺省开启）
+// g++ test.cpp -std=c++17 -fno-exceptions
+// 关闭异常,可看到可执行文件的大小的变化。
+int main()
+{
+    std::vector<int> v{1, 2, 3, 4, 5};
+    v.push_back(20);
+}