c++程序改错_expected type-specifier before ‘;’ token

#include<iostream>
#include<iomanip> 
#include<cmath>
using namespace std;
class function
{
	public:
		virtual double operator()(double x)const=0;
		virtual ~function();
};
class myfunction:public function
{
	public:
		double operator()(double x)const
		{
			return log(1.0+x)/(1.0+x*x);
		}
};
class integration
{
	public:
		virtual double operator()(double a,double b,double eps)const=0;
		virtual ~integration();
};
class trapz:public integration
{
	public:
		virtual double operator()(double x,double y,double eps)const;
		trapz(const function &f):f(f){}
	private:
		const function &f;
};
double trapz::operator() (double a,double b,double eps)const
{
	bool done=false;
	int n=1;
	int h=b-a;
	double tn=(f(a)+f(b))*h/2;//当n=1时，利用公式tn=h(f(x)+f(x+1))/2 
	double t2n;
	do
	{
		double sum=0;
		for(int k=0;k<n;k++)
		{ 
		double x=a+(k+0.5)*h;//h=(b-a)/n,xk=a+kh,t2n=h(f(xk)+f(xk+1))/4+hf(xk+1/2)/2 
		sum=sum+f(x);
	    }//进行二分，利用递推公式计算新的积分值 
	t2n=(tn+h*sum)/2.0;
	if(fabs(t2n-tn)<eps)
	done=true;
	else//进行判断，如果两次计算积分值的差在所给定的误差范围之内，二分后的积分值就是所求得的积分，若不是，则返回第二步，继续执行 
	{
		tn=t2n;
		n=n*2;
		h=h/2;
	}
	}while(!done);
	return t2n; 
}
int main()
{
	myfunction m;
	trapz t(m);
	cout<<t.operator(0,2,1e-7)<<endl;
	return 0;
}

哪位大神可以帮我看一下为什么在cout<<t.operator(0,2,1e-7)<<endl这条语句始终报错，我觉得没毛病呀，谢谢啦~

64    18    C:\Users\24864\Desktop\变步长梯形积分.cpp    [Error] expected type-specifier before '(' token