c++ - 如何在C++中异步调用静态方法？

Question

我想异步运行我的极小极大算法，这样它就不会在等待转弯时卡住用户界面。这是我需要调用的静态方法:

//ChessContext is the current state of the board
//Turn contains fromX, fromY, toX, toY when moving a piece
static Turn getBestTurn(ChessContext cc, int depth);

我已经尝试过这个:

//context is a reference to the game currently played
auto fu = std::async(std::launch::async, ChessContext::getBestTurn, context , 5);
Turn t = fu.get();

它给我一个错误说

boardview.cpp:69:23: error: no matching function for call to 'async' 
future:1712:5: note: candidate template ignored: substitution failure [with _Fn = Turn (&)(ChessContext, int), _Args = <ChessContext &, int>]:
    no type named 'type' in 'std::result_of<Turn ((ChessContext, int))(ChessContext, int)>'
future:1745:5: note: candidate template ignored: substitution failure [with _Fn = std::launch, _Args = <Turn (&)(ChessContext, int), ChessContext &, int>]:
    no type named 'type' in 'std::result_of<std::launch (Turn ()(ChessContext, int), ChessContext, int)>'

我最终希望在单独的线程上的每个可能的回合上运行该算法，或者一次在两个线程上运行该算法，看看它是否可以提高性能。

最少代码:

#include <iostream>
#include <thread>
#include <future> 

class Turn
{
};
class ChessContext 
{
public:
    ChessContext();
    ChessContext(ChessContext &cc);

    static Turn getBestTurn(ChessContext cc, int depth);
}; 

int main(){
    ChessContext context;
    auto fu = std::async(std::launch::async, ChessContext::getBestTurn, context, 5);
}

这是完整的项目 https://github.com/zlatkovnik/Super-Chesster.git

Answer 1

ChessContext 不可复制。 ChessContext(ChessContext &cc) 不是复制构造函数，您需要 ChessContext(const ChessContext &cc)。