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      std::multiplies<void>

      From cppreference.com
      <cpp‎ |utility‎ |functional
       
       
      Utilities library
       
      Function objects
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      (C++17)(C++23)
      Identity function object
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      Transparent operator wrappers
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      (C++14)
      multiplies<>
      (C++14)  
      (C++14)
      (C++14)
      (C++14)
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      Old binders and adaptors
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      Defined in header<functional>
      template<>
      class multiplies<void>;
      		(since C++14)

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

      Contents

      [edit]Member types

      Type Definition
      is_transparentunspecified

      [edit]Member functions

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

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

      template<class T,class U>

      constexprauto operator()( T&& lhs, U&& rhs)const

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

      Returns the product oflhs andrhs.

      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 omittedconstexprstd::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)
      Retrieved from "https://en.cppreference.com/mwiki/index.php?title=cpp/utility/functional/multiplies_void&oldid=173623"
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