Using boost::bind to create a function object binding a auto-release "heap" resource

I try to use boost::bind to create a function object, as well, I want to bind a object created on the HEAP to it for a delay call. The example code like below:

#include <boost/function.hpp>
#include <boost/bind.hpp>
#include <boost/noncopyable.hpp>
#include <boost/smart_ptr.hpp>
#include <boost/typeof/typeof.hpp>
#include <iostream>
using namespace boost;

class CTest : public noncopyable
{
public:
    CTest():mInt(0){ std::cout << "constructor" << std::endl; }
    ~CTest(){ std::cout << "destructor" << std::endl; }
    int mInt;
};

int getM( CTest * t )
{
    return t->mInt;
}

function<int()>开发者_JAVA百科 makeF()
{
    // create some resource on HEAP, not on STACK.
    // cause the STACK resource will be release after
    // function return.
    BOOST_AUTO( a , make_shared<CTest>() );

    // I want to use bind to create a function call
    // wrap the original function and the resource I create
    // for delay call.
    //
    // I use shared_ptr to auto release the resource when
    // the function object is gone.
    //
    // Compile ERROR!!! 
    // cannot convert parameter 1 from 'boost::shared_ptr<T>' to 'CTest *'
    //
    return bind<int>( getM , a );
}


int main(int argc, char* argv[])
{
    BOOST_AUTO( delayFunc , makeF() );
    delayFunc();
    return 0;
}

The above is just a example code. But I think it shows what I want and the current error is.

Currently, I think I can only use a function object to wrap the original function like below:

class CGetM
{
public:
    typedef int result_type;
    int operator() ( shared_ptr<CTest> t )
    {
        return getM( t.get() );
    }
};

And replace the code like this:

return bind<int>( CGetM() , a );

However, if currently I have many original function like getM, for adapting the correct arguments, wrapping it in a function object is really a large job. I don't know if there is some kind of tips or other useful util class in boost can handle such case more intelligently and elegantly ?

So any suggestion is appreciated. Thanks.

You need to use bind composition:

return bind<int>( getM, bind(&shared_ptr<CTest>::get, a) );