std::multiplies<void>
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multiplies<>
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Defined in header
<functional>
template<>
class multiplies<void>;
(since C++14)
class multiplies<void>;
std::multiplies <void> is a specialization of std::multiplies with parameter and return type deduced.
Contents
[edit] Member types
Type
Definition
is_transparent
unspecified
[edit] Member functions
operator()
(public member function)
std::multiplies<void>::operator()
template< class T, class U >
constexpr auto operator()( T&& lhs, U&& rhs ) const
Returns the product of lhs and rhs.
Parameters
lhs, rhs
-
values to multiply
Return value
std::forward <T>(lhs) * std::forward <U>(rhs).
[edit] Example
Run this code
#include <complex> #include <functional> #include <iostream> int main() { auto complex_multiplies = std::multiplies <void>{}; // "void" can be omitted constexpr std::complex z1{1.0, 2.0}, z2{3.0, 4.0}; std::cout << std::showpos << complex_multiplies(z1, z2) << ' ' << z1 * z2 << '\n' << complex_multiplies(z1, 5.) << ' ' << z1 * 5. << '\n' << complex_multiplies(5., z1) << ' ' << 5. * z1 << '\n'; }
Output:
(-5,+10) (-5,+10) (+5,+10) (+5,+10) (+5,+10) (+5,+10)