The first Boost library you should know how to use is boost::bind. Bind allows you to bind arguments to to function calls. It creates a functor (function object) that automatically can call the function associating it with the arguments.
For example, if we have the following function:
int f(int x, int y, int z) { return x + y + z; }
And then we do:
cout << bind(&f, 3, 4, 5)();
This will execute f() with arguments 3, 4, and 5.
We can also create functors that have arguments. These arguments will be pased to "placeholders" inside bind:
cout << boost::bind(&f, _1, 10, _2)(3, 9);
Will call f(3, 10, 9). We can choose the position of the arguments arbitrarily.
Bind also works with member functions:
struct Test
{
int w;
Test(int w) : w(w) {}
int f(int x, int y, int z)
{
return x + y + z + w;
}
};
Test test(30);
cout << boost::bind(&Test::f, ref(test), _3, _2, _1)(10, 20, 30);
will call test.f(30, 20, 10).
Here, the second argument of bind must be the function's object.
Since bind creates a copy of its arguments, we use boost::ref to wrap the object test so bind can store just a reference of the object. If we didn't do this, a copy of test held by the created functor.
You can use bind with functors as well.
