A First Stab at boost::bind

Boost::bind is “able to bind any argument to a specific value or route input arguments into arbitrary positions.” It’s a means of converting a function into an object that can be copied around and called at a later point, deferred callbacks for example.

An example of its power becomes evident when combined with its overloads for operator== so that you can combine with find_if (or copy_if, remove_if, etc) to call any member function of a class in a container.  See here for setting up Boost in Visual Studio environments.


#include <vector>
#include <sstream>
#include <algorithm>
#include "boost/bind.hpp"

class Record
{
public:

    Record() {}
    Record( std::string nm, int age_val )
    {
        name = nm;
        age = age_val;
    }

    std::string  GetName() const { return name; }
    unsigned int GetAge() const { return age; }

private:
    std::string name;
    unsigned int age;
};

struct DataRec
{
    std::string name;
    int age;
};

typedef DataRec data;

void main()
{
    // Set up some data
    data dat[] = { { "Andrew", 10 },
                   { "Mark",   20 },
                   { "John",   30 },
                   { "Mike",   40 } };

    // Add some records
    std::vector< Record* > rec;
    int Recs = sizeof( dat ) / sizeof( dat[ 0 ] );

    for ( int count = 0; count < Recs; count++ )
    {
        rec.push_back( new Record( dat[ count ].name,
                                   dat[ count ].age ) );
    }

    // Find the record matching the given string
    std::vector< Record* >::iterator it;

    it = std::find_if( rec.begin(),
                       rec.end(),
                       boost::bind( &Record::GetName, _1 )
                       == "Mike");

    int age = (*it)->GetAge();

    // and don't forget to delete of course...
}

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