std::minus
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                    < cpp | utility | functional
                    
                                                            
                    |   Defined in header  <functional>
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|   template< class T > struct minus;  | 
(until C++14) | |
|   template< class T = void > struct minus;  | 
(since C++14) | |
Function object for performing subtraction. Effectively calls operator- on two instances of type T.
Specializations
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 The standard library provides a specialization of  
  | 
(since C++14) | 
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
 | 
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 These member types are obtained via publicly inheriting std::binary_function<T, T, T>.  | 
(until C++11) | 
Member functions
|    operator()  | 
  returns the difference between two arguments  (public member function)  | 
std::minus::operator()
T operator()( const T& lhs, const T& rhs ) const;  | 
(constexpr since C++14) | |
Returns the difference between lhs and rhs.
Parameters
| lhs, rhs | - | values to subtract from one another | 
Return value
The result of lhs - rhs.
Exceptions
May throw implementation-defined exceptions.
Possible implementation
constexpr T operator()(const T& lhs, const T& rhs) const { return lhs - rhs; }  |