sairate
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
51 lines
1.1 KiB
C++
51 lines
1.1 KiB
C++
//
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// 5.2.unique.ptr.cpp
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// chapter 05 start pointers and memory management
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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>
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struct Foo {
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Foo() { std::cout << "Foo::Foo" << std::endl; }
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~Foo() { std::cout << "Foo::~Foo" << std::endl; }
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void foo() { std::cout << "Foo::foo" << std::endl; }
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};
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void f(const Foo &) {
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std::cout << "f(const Foo&)" << std::endl;
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}
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int main() {
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std::unique_ptr<Foo> p1(std::make_unique<Foo>());
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// p1 is not empty, prints
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if (p1) p1->foo();
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{
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std::unique_ptr<Foo> p2(std::move(p1));
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// p2 is not empty, prints
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f(*p2);
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// p2 is not empty, prints
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if(p2) p2->foo();
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// p1 is empty, no prints
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if(p1) p1->foo();
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p1 = std::move(p2);
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// p2 is empty, no prints
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if(p2) p2->foo();
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std::cout << "p2 was destroyed" << std::endl;
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}
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// p1 is not empty, prints
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if (p1) p1->foo();
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// Foo instance will be destroyed when leaving the scope
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}
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