Re: Should boost::core::string_view be made public?

From: Andrey Semashev (andrey.semashev_at_[hidden])
Date: 2024-02-08 11:45:17

On 2/8/24 14:28, Дмитрий Архипов via Boost wrote:
> boost::core::string_view is a string_view implementation that (unlike
> boost::string_view from Utility) can interconvert with
> std::string_view. This functionality was necessary for Boost.JSON to
> drop the standalone mode, because people who have access to C++17
> prefer to use std::string_view wherever they can. At the time there
> was no consensus on whether the type should be made public.
> 
> Now in addition to Boost.JSON the type is also used at least by
> Boost.URL. And recently added Charconv is also using it. So, I want to
> raise the question again: should we make the type public and refer to
> it directly in our libraries' docs, rather than considering it an
> implementation detail?

I think, if boost::core::string_view is to become public, it should come
along with deprecating and then removing boost::string_view from
Boost.Utility. As well as boost::string_ref. Having three string_view
classes (if you count boost::string_ref, four if you count
std::string_view) is a real problem for interoperability.

This is assuming the two implementations are compatible in terms of
interface and behavior.

I'll add that this will not be a free transition for other libraries
that support or use string views. For example, in Boost.Log I support
boost::string_view and boost::string_ref but not
boost::core::string_view. Not that it should be difficult to switch, but
it's work. It's more complicated if the library or tool is unmaintained.