如果我有一个实现移动语义的类:
class BigObject
{
public:
BigObject(something x = something()) { ... }
BigObject(const BigObject& other) { ... }
BigObject(BigObject&& other) { ... }
BigObject& operator=(BigObject other) { ... }
void swap(BigObject& other) { ... }
// [...]
};
auto begin = std::begin(somethingSequence); // collection doesn't matter here
auto end = std::end(somethingSequence); // collection doesn't matter here
BigObjectOutputIterator dest; // collection doesn't matter here
在 lambda 中返回 BigObject 的正确方法是什么?
std::transform(begin, end, dest,
[](something x) -> BigObject {return BigObject(x); });
或者
std::transform(begin, end, dest,
[](something x) -> BigObject&& {return std::move(BigObject(x)); });
或者
std::transform(begin, end, dest,
[](something x) -> BigObject {return std::move(BigObject(x)); });
或其他形式?
谢谢。