std::multiplies - cppreference.com (original) (raw)

| | | | | ----------------------------------- | | ------------- | | template<> class multiplies<void>; | | (since C++14) |

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

Contents

• 1 Member types
• 2 Member functions
• 3 std::multiplies::operator()
  • 3.1 Parameters
  • 3.2 Return value
  • 3.3 Example

[edit] Member types

[edit] Member functions

| | returns the product of two arguments (public member function) | | ---------------------------------------------------------------- |

std::multiplies::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 product of lhs and rhs.

Parameters

Return value

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

[edit] Example

#include #include #include   int main() { auto complex_multiplies = std::multiplies{}; // “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)