46 lines
685 B
C++
46 lines
685 B
C++
//
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// Created by light on 19-12-22.
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//
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// nrvo example
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#include <iostream>
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using namespace std;
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// Can copy and move
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class A {
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public:
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A() { cout << "Create A\n"; }
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~A() { cout << "Destroy A\n"; }
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A(const A &) { cout << "Copy A\n"; }
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A(A &&) { cout << "Move A\n"; }
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A &operator=(const A &a) {
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std::cout << "copy assignment" << std::endl;
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return *this;
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}
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A &operator=(A &&a) {
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cout << "move assignment\n";
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return *this;
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}
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};
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// 编译器可以优化 返回值移动出去
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A getA_named() {
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A a;
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return a;
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}
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int main() {
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// cout<<"拷贝"<<endl;
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// auto a = getA_named();
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cout << "赋值" << endl;
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A aa;
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aa = getA_named();
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} |