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Difference between revisions of "cpp/utility/functional/multiplies"

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template< class T >
 
template< class T >
 
struct multiplies;
 
struct multiplies;
 
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template< class T {{=}} void >
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struct multiplies;
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Function object for performing multiplication. Effectively calls {{c|operator*}} on type {{tt|T}}.
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Function object for performing multiplication. Effectively calls {{c|operator*}} on two instances of type {{tt|T}}.
  
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===Member types===
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===Specializations===
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===Member functions===
 
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{{dcl list mem fun | operator() | nolink=true | returns the product of two arguments}}
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T operator()( const T& lhs, const T& rhs ) const;
 
T operator()( const T& lhs, const T& rhs ) const;
 
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Returns the product of {{tt|lhs}} and {{tt|rhs}}.
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Returns the product of {{c|lhs}} and {{c|rhs}}.
  
 
===Parameters===
 
===Parameters===
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===Return value===
 
===Return value===
 
The result of {{c|lhs * rhs}}.
 
The result of {{c|lhs * rhs}}.
  
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T operator()(const T &lhs, const T &rhs) const  
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{
 
     return lhs * rhs;
 
     return lhs * rhs;
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Latest revision as of 21:07, 13 July 2024

 
C++
 
Utilities library
General utilities
Relational operators (deprecated in C++20)
 
Function objects
Function invocation
(C++17)(C++23)
Identity function object
(C++20)
Transparent operator wrappers
(C++14)
(C++14)
(C++14)
(C++14)  
(C++14)
(C++14)
(C++14)
(C++14)
(C++14)
(C++14)
(C++14)
(C++14)
(C++14)
(C++14)
(C++14)
(C++14)
(C++14)
(C++14)
(C++14)

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 T >
struct multiplies;
 (until C++14)
template< class T = void >
struct multiplies;
 (since C++14)

Function object for performing multiplication. Effectively calls operator* on two instances of type T.

Contents

[edit] Specializations

The standard library provides a specialization of std::multiplies when T is not specified, which leaves the parameter types and return type to be deduced.

(C++14)
 function object implementing x * y deducing parameter and return types
(class template specialization) [edit]
(since C++14)

[edit] Member types

Type Definition
result_type (deprecated in C++17)(removed in C++20) T
first_argument_type (deprecated in C++17)(removed in C++20) T
second_argument_type (deprecated in C++17)(removed in C++20) T

These member types are obtained via publicly inheriting std::binary_function<T, T, T>.

(until C++11)

[edit] Member functions

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

std::multiplies::operator()

T operator()( const T& lhs, const T& rhs ) const;
 (constexpr since C++14)

Returns the product of lhs and rhs.

Parameters

lhs, rhs - values to multiply

Return value

The result of lhs * rhs.

[edit] Exceptions

May throw implementation-defined exceptions.

Possible implementation

constexpr T operator()(const T& lhs, const T& rhs) const 
{
    return lhs * rhs;
}
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