boost::bind实践

第一部分源码为基础实践：

/*Beyond the C++ Standard Library ( An Introduction to Boost )[CN].chm*/
/*bind的用法*/

#include <iostream>
#include <algorithm>
#include <functional>
#include <vector>

#include <boost/bind/bind.hpp>
#include <boost/bind/apply.hpp>
#include <boost/smart_ptr/shared_ptr.hpp>

using namespace std;
using namespace boost;

int f(int a, int b)
{
    return a + b;
}

int g(int a, int b, int c)
{
    return a + b + c;
}

bool preFind(int a, int b)
{
    return a<b;
}
bool preFind2(int a, int b, int c)
{
    return a<b && a<c;
}
struct predicate
{
    typedef void result_type;
    void operator() (int a, int b)
    {
        cout << a << "+" << b << "=" << a+b << endl;
    }
};
struct X
{
    void f(int a)
    {
        cout << "a = " << a << endl;
    }
    void f2(int a, int b)
    {
        cout << a << "+" << b << "=" << a+b << endl;
    }
    predicate pre;
    int arrElem;
    int *parrElem;
};

void main()
{
    int arr[5] = {1, 2, 3, 4, 5};
    //int ret1 = std::count_if(arr, arr+5, boost::bind(preFind, _1, 2));
    //cout << ret1 << endl;
    //int ret2 = std::count_if(arr, arr+5, boost::bind(preFind, 2, _2));
    //cout << ret2 << endl;
    //std::for_each (arr, arr+5, boost::bind(preFind, _1, 2));
    //std::for_each (arr, arr+5, boost::bind(predicate(), _1, 2));
    //std::for_each (arr, arr+5, boost::bind(boost::type<void>(), predicate(), _1, 2));
    //std::for_each (arr, arr+5, boost::bind(preFind2, _1, 2, 3));
    //std::for_each (arr, arr+5, boost::bind(preFind2, _1, 2, _1));
    //boost::bind(preFind2, 5, _2, 3);
    //std::for_each (arr, arr+5, boost::bind(preFind2, 5, _2, 3));

    //boost::bind(preFind, _1, 2);
    //boost::bind(preFind, _2, 2);
    //boost::bind(preFind, _1, _2);
    //boost::bind(preFind, _2, _1);
    //boost::bind(preFind2, _1, _2, _3);
    //boost::bind(predicate(), _1, _2);
    //boost::bind(boost::type<void>(), predicate(), _1, _2);

    //X x;
    //boost::bind(&X::f, boost::ref(x), _1);
    //boost::bind(&X::f, _1, 1);
    //boost::bind(&X::f, _1, _2);
    //boost::bind(&X::pre, _1);
    //std::for_each (arr, arr+5, boost::bind(&X::f, x, _1));
    //std::for_each (arr, arr+5, boost::bind(&X::f2, boost::ref(x), _1, 2));
    //std::for_each (arr, arr+5, boost::bind(&X::f2, &x, _1, 2));
    //boost::shared_ptr<X> p(new X);
    //std::for_each (arr, arr+5, boost::bind(&X::f2, p, _1, 2));
    std::vector<X*> arrs;
    for (int i=0 ; i!=5 ; ++i)
    {
        arrs.push_back(new X);
    }
    std::for_each (arrs.begin(), arrs.end(), boost::bind(&X::arrElem, _1));
    std::for_each (arrs.begin(), arrs.end(), boost::bind(&X::f, _1, 2));
}

第二部分源码为实际应用：

/*Beyond the C++ Standard Library ( An Introduction to Boost )[CN].chm*/
/*bind的用法*/

#include <iostream>
#include <algorithm>
#include <functional>
#include <vector>

#include <boost/bind/bind.hpp>
#include <boost/smart_ptr/shared_ptr.hpp>

using namespace std;
using namespace boost;

class status 
{  
public:
    std::string name_;  
    bool ok_;
public:  
    status(const std::string& name):name_(name),ok_(true) {}  
    void break_it() {    ok_=false;  }  
    bool is_broken() const {    return ok_;  }  
    void report() const 
    {    
        std::cout << name_.c_str() << " is " << (ok_ ? "working nominally":"terribly broken") << std::endl;  
    }
};

void nine_arguments(  int i1,int i2,int i3,int i4,  int i5,int i6,int i7,int i8, int i9)
{  
    std::cout << i1 << i2 << i3 << i4 << i5 << i6 << i7 << i8 << i9 << '
';
}
int main() 
{  
    int i1=1,i2=2,i3=3,i4=4,i5=5,i6=6,i7=7,i8=8,i9=9;  
    (boost::bind(&nine_arguments,_9,_2,_1,_6,_3,_8,_4,_5,_7))(i1,i2,i3,i4,i5,i6,i7,i8,i9);


    //std::vector<status> statuses;
    //statuses.push_back(status("status 1"));
    //statuses.push_back(status("status 2"));
    //statuses.push_back(status("status 3"));
    //statuses.push_back(status("status 4"));
    //statuses[1].break_it();
    //statuses[2].break_it();
    ////method 1:
    //for (std::vector<status>::iterator it=statuses.begin();  it!=statuses.end();++it) 
    //{  
    //    it->report();
    //}
    ////method 2: ok
    //std::for_each(  statuses.begin(),  statuses.end(),  std::mem_fun_ref(&status::report));
    ////method 3: ok
    //std::for_each(  statuses.begin(),  statuses.end(),  boost::bind(&status::report, _1));
    ////others ok
    //std::for_each(  statuses.begin(),  statuses.end(),  boost::bind(&status::name_, _1));

    //std::vector<status*> p_statuses;
    //p_statuses.push_back(new status("status 1"));
    //p_statuses.push_back(new status("status 2"));
    //p_statuses.push_back(new status("status 3"));
    //p_statuses.push_back(new status("status 4"));
    //p_statuses[1]->break_it();
    //p_statuses[2]->break_it();
    ////method 2: ok
    //std::for_each(  p_statuses.begin(),  p_statuses.end(),  std::mem_fun(&status::report));
    ////method 3: ok
    //std::for_each(  p_statuses.begin(),  p_statuses.end(),  boost::bind(&status::report, _1));

    std::vector<boost::shared_ptr<status> > s_statuses;
    s_statuses.push_back(  boost::shared_ptr<status>(new status("status 1")));
    s_statuses.push_back(  boost::shared_ptr<status>(new status("status 2")));
    s_statuses.push_back(  boost::shared_ptr<status>(new status("status 3")));
    s_statuses.push_back(  boost::shared_ptr<status>(new status("status 4")));
    s_statuses[1]->break_it();
    s_statuses[2]->break_it();
    //method 2: error
    //std::for_each(  s_statuses.begin(),  s_statuses.end(),  std::mem_fun(&status::report));
    //method 3: ok
    std::for_each(  s_statuses.begin(),  s_statuses.end(),  boost::bind(&status::report, _1));


}