std::basic_string_view<CharT,Traits>::copy
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                    < cpp | string | basic string view
                    
                                                            
                    | size_type copy( CharT* dest, size_type count, size_type pos = 0 ) const; | (since C++17) (until C++20) | |
| constexpr size_type copy( CharT* dest, size_type count, size_type pos = 0 ) const; | (since C++20) | |
Copies the substring [pos, pos + rcount) to the character array pointed to by dest, where rcount is the smaller of count and size() - pos.
Equivalent to Traits::copy(dest, data() + pos, rcount).
Parameters
| dest | - | pointer to the destination character string | 
| pos | - | position of the first character | 
| count | - | requested substring length | 
Return value
Number of characters copied
Exceptions
std::out_of_range if pos > size().
Complexity
Linear in rcount.
See also
| returns a substring (public member function) |