std::pmr::memory_resource::is_equal
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                    < cpp | memory | memory resource
                    
                                                            
                    |   bool is_equal( const memory_resource& other ) const noexcept;  | 
(since C++17) | |
Compares *this for equality with other. Two memory_resources compare equal if and only if memory allocated from one memory_resource can be deallocated from the other and vice versa.
Equivalent to return do_is_equal(other);.
See also
|    [virtual]  | 
   compare for equality with another memory_resource (virtual private member function)  |