C++ keywords: export
From cppreference.com
                    
                                        
                    
                    
                                                            
                    Usage
| 
 Used to mark a template definition exported, which allows the same template to be declared, but not defined, in other translation units.  | 
(until C++11) | 
| 
 The keyword is unused and reserved.  | 
(since C++11) (until C++20)  | 
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 Marks a declaration, a group of declarations, or another module as exported by the current module.  | 
(since C++20) |