问题
So I have a situation where I need to store a vector of an abstract type, as I understand this requires the usage of a vector of unique_ptrs or similar.
So in order to move about instances of the class which contains the vector of unique_ptrs, I need to define a move constructor which I have done.
However as demonstrated by the example below, this seems to disagree with the compiler (msvc) which gives me the following error.
Error 1 error C2280: 'std::unique_ptr>::unique_ptr(const std::unique_ptr<_Ty,std::default_delete<_Ty>> &)' : attempting to reference a deleted function
class SomeThing{
};
class Foo{
public:
Foo(){
}
Foo(const Foo&& other) :
m_bar(std::move(other.m_bar))
{};
std::vector<std::unique_ptr<SomeThing>> m_bar;
};
int main(int argc, char* argv[])
{
Foo f;
return 0;
}
回答1:
You can't move from a const thing, because a move involves mutation of the source.
Therefore, a copy is being attempted instead. And, as you know, that's impossible here.
Your move constructor should look like this, with no const:
Foo(Foo&& other)
: m_bar(std::move(other.m_bar))
{}
来源：https://stackoverflow.com/questions/31413197/moving-a-vector-of-unique-ptrt