Standard C++ Library Class Reference

Description
Because so many functions provided by the standard library take other functions as arguments,
the library includes classes that let you build new function objects out of old ones. Both bind1st()
and bind2nd() are functions that take as arguments a binary function object f and a value x, and
return, respectively, classes binder1st and binder2nd. The underlying function object must be a
subclass of binary_function.
Class binder1st binds the value to the first argument of the binary function, and binder2nd does
the same thing for the second argument of the function. The resulting classes can be used in
place of a unary predicate in other function calls.
For example, you could use the count_if algorithm to count all elements in a vector that are less
than or equal to 7, using the following:
count_if (v.begin, v.end, bind1st(greater<int> (),7), littleNums)
This function adds one to littleNums each time the predicate is true, i.e., each time 7 is greater
than the element.
Interface
// Class binder1st
template <class Operation>
class binder1st
: public unary_function<typename
Operation::second_argument_type,
typename Operation::result_type>
{
public:
typedef typename unary_function<typename
Operation::second_argument_type, typename
Operation::result_type>::argument_type argument_type;
typedef typename unary_function<typename
Operation::second_argument_type, typename
Operation::result_type>::result_type result_type;
binder1st(const Operation&,
const typename Operation::first_argument_type&);
result_type operator() (const argument_type&) const;
};
// Class binder2nd
template <class Operation>
class binder2nd
: public unary_function<typename
Operation::first_argument_type,