std::modulus<void>

From cppreference.com
< cpp‎ | utility‎ | functional
 
 
Utilities library
General utilities
Relational operators (deprecated in C++20)
 
Function objects
Function invocation
(C++17)(C++23)
Identity function object
(C++20)
Transparent operator wrappers
(C++14)
(C++14)
(C++14)
(C++14)  
(C++14)
modulus<>
(C++14)
(C++14)
(C++14)
(C++14)
(C++14)
(C++14)
(C++14)
(C++14)

Old binders and adaptors
(until C++17*)
(until C++17*)
(until C++17*)
(until C++17*)  
(until C++17*)
(until C++17*)(until C++17*)(until C++17*)(until C++17*)
(until C++20*)
(until C++20*)
(until C++17*)(until C++17*)
(until C++17*)(until C++17*)

(until C++17*)
(until C++17*)(until C++17*)(until C++17*)(until C++17*)
(until C++20*)
(until C++20*)
 
Defined in header <functional>
template<>
class modulus<void>;
(since C++14)

std::modulus<void> is a specialization of std::modulus with parameter and return type deduced.

Nested types

Nested type Definition
is_transparent unspecified

Member functions

operator()
returns the modulus of two arguments
(public member function)

std::modulus<void>::operator()

template< class T, class U >

constexpr auto operator()( T&& lhs, U&& rhs ) const

    -> decltype(std::forward<T>(lhs) % std::forward<U>(rhs));

Returns the remainder of the division of lhs by rhs.

Parameters

lhs, rhs - values to divide

Return value

std::forward<T>(lhs) % std::forward<U>(rhs).

Example

#include <functional>
#include <iostream>
 
struct M
{
    M(int x) { std::cout << "M(" << x << ");\n"; }
    M() {}
};
 
auto operator%(M, M) { std::cout << "operator%(M, M);\n"; return M{}; }
auto operator%(M, int) { std::cout << "operator%(M, int);\n"; return M{}; }
auto operator%(int, M) { std::cout << "operator%(int, M);\n"; return M{}; }
 
int main()
{
    M m;
 
    // 42 is converted into a temporary object M{42}
    std::modulus<M>{}(m, 42);    // calls operator%(M, M)
 
    // no temporary object
    std::modulus<void>{}(m, 42); // calls operator%(M, int)
    std::modulus<void>{}(42, m); // calls operator%(int, M)
}

Output:

M(42);
operator%(M, M);
operator%(M, int);
operator%(int, M);