std::plus<void>

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plus<>
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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++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 plus< void > ;
(since C++14)

std::plus<void> is a specialization of std::plus

Member types

Type Definition
is_transparent unspecified

Member functions

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

std::plus<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 sum of lhs and rhs.

Parameters

lhs, rhs - values to sum

Return value

std::forward <T> (lhs) + std::forward <U> (rhs)

Example

Run this code
#include <functional>
#include <iostream>
 
int main()
{
    auto string_plus = std::plus<void>{}; // “void” can be omitted
    std::string a = "Hello ";
    const char* b = "world";
    std::cout << string_plus(a, b) << '\n';
}

Output: 

Hello world
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