std::less
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                    < cpp | utility | functional
                    
                                                            
                    |   Defined in header <functional>
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|   template< class T > struct less;  | 
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Function object for performing comparisons. Uses operator< on type T.
Contents | 
[edit] Notes
If the built-in operator< does not provide total order for pointers, a partial specialization of std::less for pointer types is provided, which guarantees total order.
[edit] Member types
| type | definition | 
| result_type | bool | 
| first_argument_type | T | 
| second_argument_type | T | 
[edit] Member functions
|    operator()  | 
   checks if the first argument is less than the second  (public member function)  | 
std::less::operator()
|   bool operator()( const T& lhs, const T& rhs ) const;  | 
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Checks whether lhs is less than rhs.
Parameters
| lhs, rhs | - | values to compare | 
Return value
true if lhs < rhs, false otherwise.
Exceptions
(none)
Possible implementation
bool operator()(const T &lhs, const T &rhs) const { return lhs < rhs; }  | 
[edit] See also
|    (C++11)  | 
   provides mixed-type owner-based ordering of shared and weak pointers   (class template)  |