keywords: VS2019, Code Analysis, Code Checking, std::move

Docs

std::move
https://en.cppreference.com/w/cpp/utility/move

std::forward
https://en.cppreference.com/w/cpp/utility/forward

Move assignment operator
https://en.cppreference.com/w/cpp/language/move_assignment

Move with vector::push_back
https://stackoverflow.com/a/11572684/1645289

Tools

New Code Analysis Checks in Visual Studio 2019: use-after-move and coroutine
https://blogs.msdn.microsoft.com/vcblog/2019/01/28/new-code-analysis-checks-in-visual-studio-2019-use-after-move-and-coroutine

Move constructors(since C++11)
https://en.cppreference.com/w/cpp/language/move_constructor

Examples

std::move with reference
#include <vector>
#include <iostream>

struct A {
    int a[100];
    A() {}
    A(const A& other) {
        std::cout << "copy" << std::endl;
    }
    A(A&& other) {
        std::cout << "move" << std::endl;
    }
};

void foo(const A& a) {
    std::vector<A> vA;
    vA.push_back(std::move(a));
}

void bar(A&& a) {
    std::vector<A> vA;
    vA.push_back(std::move(a));
}

void baz(A& a) {
    std::vector<A> vA;
    vA.push_back(std::move(a));
}

int main() {
    A a;
    foo(a);            // "copy"
    foo(std::move(a)); // "copy"
    bar(std::move(a)); // "move"
    //baz(std::move(a)); // compilation error!!
}

origin: Does std::move work with lvalue references?
https://stackoverflow.com/a/49305927/1645289

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