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.
[code language="cpp"]
#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...
}
[/code]
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