std::plus<void>
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Defined in header 
 
 
<functional> 
 template<>
class plus<void>;
 
 (since C++14) 
class plus<void>;
std::plus <void> is a specialization of std::plus with parameter and return type deduced.
Contents
[edit] Member types
 Type
 Definition
is_transparent
 unspecified
[edit] Member functions
std::plus<void>::operator()
template< class T, class U >
 
 
constexpr auto operator()( T&& lhs, U&& rhs ) const
Returns the sum of lhs and rhs.
Parameters
 lhs, rhs
 -
 values to sum
Return value
std::forward <T>(lhs) + std::forward <U>(rhs).
[edit] 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