[英]Overloading a bool operator with a member function
I have a class like this: 我有这样的课:
class AI
{
private:
struct Comparator
{
bool operator()(const Town* lfs, const Town* rhs)
{
return GetHeuristicCost(lfs) > GetHeuristicCost(rhs);
}
};
int GetHeuristicCost(const Town* town);
// constructor and variables
};
GetHeuristicCost
returns the heuristic from the town parameter to the exit
of the path. GetHeuristicCost
返回从Town参数到路径exit
的启发式方法。
What I am trying to do is overload the bool operator for a priority queue but it gives me the error 我想做的是将布尔运算符重载到优先级队列,但这给了我错误
a nonstatic member reference must be relative to a specific object
I know why it is giving me this error but what I don't know is how to use a nonstatic function inside the Comparator
struct. 我知道为什么会给我这个错误,但是我不知道如何在
Comparator
结构中使用非静态函数。
GetHeuristicCost
must be nonstatic GetHeuristicCost
必须GetHeuristicCost
静态 GetHeuristicCost
inside the Town
class to no avail GetHeuristicCost
Town
类中无济于事 I need to overload the operator with a struct because I need to use two different bool overloadings on the ()
for two different circumstances but with the same parameters (two Towns). 我需要用一个结构重载运算符,因为我需要在
()
上使用两个不同的布尔重载,用于两种不同的情况,但参数相同(两个镇)。 In other words I need the struct so I can't do this: 换句话说,我需要该结构,所以我不能这样做:
bool operator()(const Town* lfs, const Town* rhs) { return GetHeuristicCost(lfs) > GetHeuristicCost(rhs); bool operator()(const Town * lfs,const Town * rhs){返回GetHeuristicCost(lfs)> GetHeuristicCost(rhs ;; }
}
Basically I plan on having two structs like this: 基本上我打算有两个这样的结构:
struct Comparator1
{
bool operator()(const Town* lfs, const Town* rhs)
{
return GetHeuristicCost(lfs) > GetHeuristicCost(rhs);
}
};
struct Comparator2
{
bool operator()(const Town* lfs, const Town* rhs)
{
return GetHeuristicCost(lfs) + GetTotalCost (lfs, rhs) > GetHeuristicCost(rhs) + GetTotalCost (lfs, rhs);
}
};
You need to construct instances of the Comparator nested class with a pointer/reference to their "outer" class instance. 您需要使用指向其“外部”类实例的指针/引用来构造Comparator嵌套类的实例。
class AI
{
private:
struct Comparator
{
const AI &outer;
Comparator(const AI &o):outer(o){}
bool operator()(const Town* lfs, const Town* rhs)const
{
return outer.GetHeuristicCost(lfs) > outer.GetHeuristicCost(rhs);
}
};
int GetHeuristicCost(const Town* town)const;
};
// how to use in code:
AI::Comparator comp(*this);
priority_queue<Town*, vector<Town*>, AI::Comparator> priorityQueue(comp);
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.