Noncopyable types, borrowing, consuming, etc have been a part of the language for a while. Yet, there is no accessible documentation on these topics for someone learning the language (yeah, there is manifesto and proposals - but these are not really suitable for "learning" in (not only) my opinion. Is there a reason these are not part of the official documentation yet? If there is no reason, are there any plans to include them in near future? I believe that it is an obstacle for people who want to adopt the language and use it effectively for systems programming or just be able to tune performance where it is relevant.
PS: If this is only time/workforce issue, I'd happily write these parts myself, if someone more knowledgeable than me on the subject and the language would be willing to review and correct it.
Looks like the ownership modifiers are documented in The Swift Programming Language under the "Reference Manual" section, and that keeping it there was a conscious decision. However, I'd imagine that authors would be open to hearing about alternative viewpoints and how it could be improved!
If you have changes you'd like to add to TSPL, I'm happy to help you get technical and editorial review. Feel free to start small, filling in some minor gaps, to learn the process. For bigger changes, like a new section, please share your outline on the forums, like you'd pitch a Swift Evolution proposal. More contribution details are in the book's repo.
PR 351 mostly just adds documentation of the ~Protocol syntax to suppress an implicit conformance/requirement. A conceptual explanation of noncopyable and nonescapable types, to complement their API reference pages, would be a useful follow-on PR.
The problem is that documentation is not easy to search. (At least, there is no obvious way to do it - filter doesn't find specific words.). An intuitive search option (if there is an not-intuitive one, I'd like to learn about it - for now I have to resort to searching google with site:docs.swift.org prefix) or at least a PDF version of the book easily downloadable from documentation site (or github) would be really appreciated.
Here are GitHub issue tracking an offline version of TSPL and the corresponding/blocking DocC issue. The first page includes an example PDF and ePUB version of the book from a member of the open-source community.