Function Object
A binary function object that returns true if its first argument equals its second.
None
#include <functional> template <class T> struct equal_to;
equal_to is a binary function object. Its operator() returns true if x is equal to y. You can pass an equal_to object to any algorithm that requires a binary function. For example, the transform algorithm applies a binary operation to corresponding values in two collections and stores the result. equal_to would be used in that algorithm in the following manner:
vector<int> vec1; vector<int> vec2; vector<int> vecResult; . . . transform(vec1.begin(), vec1.end(), vec2.begin(), vecResult.begin(), equal_to<int>());
After this call to transform, vecResult(n) contains a 1 if vec1(n) was equal to vec2(n) or a 0 if vec1(n) was not equal to vec2(n).
template <class T> struct equal_to : binary_function<T, T, bool>
binary_function, Function Objects