diff --git a/README.md b/README.md index 563544c..6612bc4 100644 --- a/README.md +++ b/README.md @@ -44,25 +44,31 @@ #### 2.2 [C++2.0新特性](./c++2.0/) - [Variadic Templates](./c++2.0/variadic) + - Spaces in Template Expressions -```cpp -vector > //ok in each C++ version -vector> // before c++ 11 error error: ‘>>’ should be ‘> >’ within a nested template argument list,c++11后可以正常通过 -``` + ```cpp + vector > //ok in each C++ version + vector> // before c++ 11 error error: ‘>>’ should be ‘> >’ within a nested template argument list,c++11后可以正常通过 + ``` - [nullptr and nullptr_t](./c++2.0/nullptr.cpp) + - [Automatic Type Deduction with auto](./c++2.0/auto.cpp) + - [Uniform Initialization ](./c++2.0/uniform_initialization.cpp) + - [initializer_list](./c++2.0/initializer.cpp) + - [explicit for ctors taking more than one argument](./c++2.0/explicit.cpp) + - [range-based for statement](./c++2.0/auto.cpp) -```cpp -for(decl:col) { - statement -} -``` + ```cpp + for(decl:col) { + statement + } + ``` - [=default,=delete](./c++2.0/default_delete.cpp) @@ -75,14 +81,23 @@ for(decl:col) { - [template_template.cpp](./c++2.0/template_template.cpp) - [template template parameter](./c++2.0/template_template.cpp) + - [type alias](./c++2.0/type_alias.cpp) + - [noexcept](./c++2.0/noexcept.cpp) + - [override](./c++2.0/override.cpp) + - [final](./c++2.0/final.cpp) + - [decltype](./c++2.0/decltype.cpp) + - [lambda](./c++2.0/lambda.cpp) + - [Rvalue reference](./c++2.0/rvalue.cpp) + - [move aware class](./c++2.0/move.cpp) + - 容器-结构与分类 - (1) 序列式容器包括：array(C++2.0新引入),vector,deque,list,forward_list(C++2.0新引入) @@ -90,9 +105,10 @@ for(decl:col) { - (3) 无序容器(C++2.0新引入,更换原先hash_xxx为unordered_xxx)包括：unordered_map/unordered_multimap,unordered_set/unordered_multiset - [Hash Function](./c++2.0/hash.cpp) + - [tuple](./c++2.0/tuple.cpp) -学习资料：https://www.bilibili.com/video/av51863195?from=search&seid=3610634846288253061 + 学习资料：https://www.bilibili.com/video/av51863195?from=search&seid=3610634846288253061 #### 2.3 [C++并发编程v1](./c++2.0/./concurrency_v1) @@ -148,6 +164,7 @@ for(decl:col) { - [译期能做些什么？一个完整的计算世界](./modern_C++_30/compilercompute) - [SFINAE：不是错误的替换失败是怎么回事?](./modern_C++_30/SFINAE) - [constexpr：一个常态的世界](./modern_C++_30/constexpr) +- [函数对象和lambda：进入函数式编程](./modern_C++_30/functionLambda) ### 4.拓展部分 @@ -165,31 +182,33 @@ for(decl:col) { - [C++中如何将string类型转换为int类型？](./basic_content/extent/string_int.md) -### 5.自己写的工具 +### 5.工具篇 - [容器快捷输出工具](./tool/output) -对吴老师的代码进行了修改，[点击此处直通代码](./tool/output/output_container.h) + 对吴老师的代码进行了修改，[点击此处直通代码](./tool/output/output_container.h) -输入： + 输入： -```cpp -map mp{ - {1, 1}, - {2, 4}, - {3, 9}}; - cout << mp << endl; -``` + ```cpp + map mp{ + {1, 1}, + {2, 4}, + {3, 9}}; + cout << mp << endl; + ``` -输出结果显示： + 输出结果显示： -```cpp -{ 1 => 1, 2 => 4, 3 => 9 } -``` + ```cpp + { 1 => 1, 2 => 4, 3 => 9 } + ``` -感谢吴老师的代码，原代码： +- 像Python一样简单输出 + - [像Python一样玩C/C++](./tool/像Python一样玩CC++.md) -> https://github.com/adah1972/output_container/blob/master/output_container.h +- 观察编译过程变化 + - [https://cppinsights.io](https://cppinsights.io/) ### 6.代码运行 diff --git a/modern_C++_30/functionLambda/adder.cpp b/modern_C++_30/functionLambda/adder.cpp new file mode 100644 index 0000000..34a2849 --- /dev/null +++ b/modern_C++_30/functionLambda/adder.cpp @@ -0,0 +1,34 @@ +// +// Created by light on 20-1-11. +// +#include + +using namespace std; + +struct adder { + adder(int n) : n_(n) {} + + int operator()(int x) const { + return x + n_; + } + +private: + int n_; +}; + +int main() { + auto add_2 = adder(2); + + // x+2 + cout << add_2(3) << endl; + + auto t = bind1st(plus(), 2); + cout << t(1) << endl; + // 上述的C++98 + binder2nd > a2(plus(), 2); + cout << a2(3) << endl; + + cout << [](int x) { return x * x; }(3) << endl; + return 0; + // lambda表达式默认就是constexpr函数 +} \ No newline at end of file diff --git a/modern_C++_30/functionLambda/autoLambda.cpp b/modern_C++_30/functionLambda/autoLambda.cpp new file mode 100644 index 0000000..6da7199 --- /dev/null +++ b/modern_C++_30/functionLambda/autoLambda.cpp @@ -0,0 +1,64 @@ +// +// Created by light on 20-1-11. +// + + +#include +#include +#include +#include + +using namespace std; + +int get_count() { + static int count = 0; + return ++count; +} + +class task { +public: + task(int data) : data_(data) {} + + /** + * this 标明按引用捕获外围对象（针对 lambda 表达式定义出现在一个非静态类成员内的情况）； + * 注意默认捕获符 = 和 & 号可以自动捕获 this（并且在 C++20 之前，在 = 后写 this 会导致出错） + * 本例子两次都按照第二次输出(this_thread::sleep_for(100ms); + * this 标明按引用捕获外围对象 + * + * + * *this 标明按值捕获外围对象（针对 lambda 表达式定义出现在一个非静态类成员内的情况；C++17 新增语法） + * 本例子正常输出 + */ + auto lazy_launch() { + return + [*this, count = get_count()]() + mutable { + ostringstream oss; + oss << "Done work " << data_ + << " (No. " << count + << ") in thread " + << this_thread::get_id() + << '\n'; + msg_ = oss.str(); + calculate(); + }; + } + + void calculate() { + this_thread::sleep_for(100ms); + cout << msg_; + } + +private: + int data_; + string msg_; +}; + +int main() { + auto t = task{37}; + thread t1{t.lazy_launch()}; + thread t2{t.lazy_launch()}; + t1.join(); + t2.join(); +} + diff --git a/modern_C++_30/functionLambda/function.cpp b/modern_C++_30/functionLambda/function.cpp new file mode 100644 index 0000000..66d9086 --- /dev/null +++ b/modern_C++_30/functionLambda/function.cpp @@ -0,0 +1,32 @@ +// +// Created by light on 20-1-11. +// + +#include +#include +#include + +using namespace std; + +int main() { + + map> + op_dict{ + {"+", + [](int x, int y) { + return x + y; + }}, + {"-", + [](int x, int y) { + return x - y; + }}, + {"*", + [](int x, int y) { + return x * y; + }}, + {"/", + [](int x, int y) { + return x / y; + }}, + }; +} \ No newline at end of file diff --git a/tool/像Python一样玩CC++.md b/tool/像Python一样玩CC++.md new file mode 100644 index 0000000..612ef1e --- /dev/null +++ b/tool/像Python一样玩CC++.md @@ -0,0 +1,117 @@ +# 像Python一样玩C/C++ + +在Python中我们可以使用`Jupyter Notebook`直接看到结果，例如： + +```c +l = [1,2] +l +``` + +直接输出： + +``` +[1,2] +``` + +那当使用C++的时候，例如： + +```cpp +map mp{ + {"one", 1}, + {"two", 2}, + {"three", 3}, + {"four", 4} +}; +``` + +如果要输出，就得循环遍历，可否直接输出结果呢？ + +so easy!!! `Jupyter Notebook`可以解决一切问题，哈哈～ + +## 如何在Jupyter中玩C++？ + +在github上有一个仓库，如下所示： + +> https://github.com/QuantStack/xeus-cling + +`xeus-cling` 是一个用于C++的Jupyter内核，基于C++解释器和Jupyter协议xeus的原生实现。 + +目前，支持Mac与Linux，但不支持Windows。 + +安装也是非常简单，首先安装好Anaconda，在里面创建一个虚拟环境： + +``` +conda create -n cling +``` + +切换进去： + +``` +conda activate cling +``` + +给新环境安装`jupyter`和`notebook` + +``` +conda install jupyter notebook +``` + +使用`conda-forge`安装`xeus-cling` + +``` +conda install xeus-cling -c conda-forge +``` + +为了加速安装，请记得给Anaconda配置源！ + +检查是否安装好了内核(kernel)： + +``` +jupyter kernelspec list +``` + +输出： + +```cpp +python3 /home/xxx/anaconda3/envs/cling/share/jupyter/kernels/python3 +xcpp11 /home/xxx/anaconda3/envs/cling/share/jupyter/kernels/xcpp11 +xcpp14 /home/xxx/anaconda3/envs/cling/share/jupyter/kernels/xcpp14 +xcpp17 /home/xxx/anaconda3/envs/cling/share/jupyter/kernels/xcpp17 +``` + +打开`Jupyter Notebook`，就可以看到看到kernel了。 + +启动`Jupyter Notebook`： + +``` +jupyter-notebook +``` + +## 如何在Jupyter中玩C？ + +只需要安装c kernel即可！ + +可以直接在当前环境中创建c kernel，也可以新开一个环境安装，下面是在当前环境中直接安装。 + +``` +pip install jupyter-c-kernel +install_c_kernel +jupyter kernelspec list +``` + +此时，就输出： + +```cpp +c /home/light/anaconda3/envs/cling/share/jupyter/kernels/c +python3 /home/light/anaconda3/envs/cling/share/jupyter/kernels/python3 +xcpp11 /home/light/anaconda3/envs/cling/share/jupyter/kernels/xcpp11 +xcpp14 /home/light/anaconda3/envs/cling/share/jupyter/kernels/xcpp14 +xcpp17 /home/light/anaconda3/envs/cling/share/jupyter/kernels/xcpp17 +``` + +启动`Jupyter Notebook`： + +``` +jupyter-notebook +``` +