How to correctly create std::string from a std::string_view?

There is no need to use the c’tor taking a range. std::string has a constructor that operates in terms of std::string_view, number 10 in the list. The effect of which is

template < class T >
explicit basic_string( const T& t, const Allocator& alloc = Allocator() ); 

Implicitly converts t to a string view sv as if by std::basic_string_view<CharT, Traits> sv = t;, then initializes the string with the contents of sv, as if by basic_string(sv.data(), sv.size(), alloc). This overload only participates in overload resolution if std::is_convertible_v<const T&, std::basic_string_view<CharT, Traits>> is true and std::is_convertible_v<const T&, const CharT*> is false.

Since both conditions hold for std::string_view itself, we can write the call to loadData as simply:

loadData( std::string( symbol.strVw() ) );