std::filesystem::operator/(std::filesystem::path)
From cppreference.com
                    
                                        
                    < cpp | filesystem | path
                    
                                                            
                    | Defined in header  <filesystem> | ||
| path operator/( const path& lhs, const path& rhs ); | (since C++17) | |
Concatenates two path components using the preferred directory separator if appropriate (see operator/= for details).
Effectively returns path(lhs) /= rhs.
Parameters
| lhs, rhs | - | paths to concatenate | 
Return value
The result of path concatenation.
Exceptions
noexcept specification:  
noexcept
  Example
| This section is incomplete Reason: no example | 
See also
| appends elements to the path with a directory separator (public member function) |