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c34823a3bd
- 新增现代 C++ 教程的 Preface 章节，包括英文和中文版本 - 添加 C++ Primer 练习代码 - 新增 Learn C++ 教程的 C++ 开发简介章节 - 添加头文件解析文档 - 更新 mkdocs.yml，包含新教程的目录结构 - 修改项目设置，使用 Python 3.10环境
63 lines
1.5 KiB
C++
63 lines
1.5 KiB
C++
//
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// 3.1.lambda.basic.cpp
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// chapter 03 runtime enhancement
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// modern c++ tutorial
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//
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// created by changkun at changkun.de
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// https://github.com/changkun/modern-cpp-tutorial
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//
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#include <iostream>
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#include <memory> // std::make_unique
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#include <utility> // std::move
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void lambda_value_capture() {
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int value = 1;
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auto copy_value = [value] {
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return value;
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};
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value = 100;
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auto stored_value = copy_value();
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std::cout << "stored_value = " << stored_value << std::endl;
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// At this moment, stored_value == 1, and value == 100.
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// Because copy_value has copied when its was created.
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}
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void lambda_reference_capture() {
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int value = 1;
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auto copy_value = [&value] {
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return value;
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};
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value = 100;
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auto stored_value = copy_value();
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std::cout << "stored_value = " << stored_value << std::endl;
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// At this moment, stored_value == 100, value == 100.
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// Because copy_value stores reference
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}
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void lambda_expression_capture() {
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auto important = std::make_unique<int>(1);
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auto add = [v1 = 1, v2 = std::move(important)](int x, int y) -> int {
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return x+y+v1+(*v2);
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};
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std::cout << add(3,4) << std::endl;
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}
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void lambda_generic() {
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auto generic = [](auto x, auto y) {
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return x+y;
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};
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std::cout << generic(1, 2) << std::endl;
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std::cout << generic(1.1, 2.2) << std::endl;
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}
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int main() {
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lambda_value_capture();
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lambda_reference_capture();
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lambda_expression_capture();
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lambda_generic();
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return 0;
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}
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