# 20 General utilities library [utilities]

## 20.8 Function objects [function.objects]

### 20.8.4 Arithmetic operations [arithmetic.operations]

The library provides basic function object classes for all of the arithmetic operators in the language ([expr.mul], [expr.add]).

``` template <class T> struct plus { T operator()(const T& x, const T& y) const; typedef T first_argument_type; typedef T second_argument_type; typedef T result_type; }; ```

operator() returns x + y.

``` template <class T> struct minus { T operator()(const T& x, const T& y) const; typedef T first_argument_type; typedef T second_argument_type; typedef T result_type; }; ```

operator() returns x - y.

``` template <class T> struct multiplies { T operator()(const T& x, const T& y) const; typedef T first_argument_type; typedef T second_argument_type; typedef T result_type; }; ```

operator() returns x * y.

``` template <class T> struct divides { T operator()(const T& x, const T& y) const; typedef T first_argument_type; typedef T second_argument_type; typedef T result_type; }; ```

operator() returns x / y.

``` template <class T> struct modulus { T operator()(const T& x, const T& y) const; typedef T first_argument_type; typedef T second_argument_type; typedef T result_type; }; ```

operator() returns x % y.

``` template <class T> struct negate { T operator()(const T& x) const; typedef T argument_type; typedef T result_type; }; ```

operator() returns -x.