Function Adaptor
Function adaptor used to reverse the sense of a binary predicate function object.
#include <functional>
template <class Predicate> binary_negate<Predicate> not2 (const Predicate& pred);
not2 is a function adaptor, known as a negator, that takes a binary predicate function object as its argument and returns a binary predicate function object that is the complement of the original. binary_negate is a function object class that provides a return type for the not2 negator.
Note that not2 works only with function objects that are defined as subclasses of the class binary_function.
binary_function, binary_negate, Negators, not1, pointer_to_binary_function, unary_negate