Update links in redirects

[mbrubeck]

Link directly to the 1.30 versions, since the relative links no longer work.

[mbrubeck]

I guess we should make these link to the 2018 edition where available

[mbrubeck]

Would you prefer to include both Second Edition and "Current Edition" links, or just Current Edition?

These redirects were originally in place to preserve old links to the first edition book, so I don't think they need to link to every edition. Just linking to the original content (First Edition) and the latest content (Current Edition) seems best.

[mbrubeck]

Updated so that each file has "First Edition" and "Current Edition" links where possible (no Second Edition).

[carols10cents]

Hi Matt :) I agree that the places that say "second edition" should say "current edition" and link to the current edition instead, as you've done here. However,

Link directly to the 1.30 versions, since the relative links no longer work.

Can you clarify what you mean by "the relative links no longer work"? If I do rustup docs with Rust 1.31.0 and then visit, say:

file:///Users/carolnichols/.rustup/toolchains/stable-x86_64-apple-darwin/share/doc/rust/html/book/deref-coercions.html

I get a page that says:

Here are the relevant sections in the new and old books:

    In the second edition: Ch 15.02 — Treating Smart Pointers like Regular References with the Deref Trait
    In the first edition: Ch 3.33 — Deref coercions

The first edition link goes to file:///Users/carolnichols/.rustup/toolchains/stable-x86_64-apple-darwin/share/doc/rust/html/book/first-edition/deref-coercions.html, which says:

Deref coercions

The first edition of the book is no longer distributed with Rust's documentation.

If you came here via a link or web search, you may want to check out the current version of the book instead.

If you have an internet connection, you can find a copy distributed with Rust 1.30.

And "find a copy distributed with Rust 1.30" links to https://doc.rust-lang.org/1.30.0/book/first-edition/deref-coercions.html, as you have here.

So I do think this is working the way @steveklabnik intended? Is it the extra click and the insinuation that there's going to be content there and then isn't that makes it seem like it doesn't work?

[mbrubeck]

Is it the extra click and the insinuation that there's going to be content there and then isn't that makes it seem like it doesn't work?

Yeah, exactly. This PR links directly to the content, instead of to a second old/redirected URL where you have to click through an extra link.

[carols10cents]

Ok, I see. I do like the extra "If you have an internet connection" bit that's on the redirect pages, because not shipping the first edition with Rust is a change... wdyt about working that in on the redirect pages?

[mbrubeck]

I don't think there's a common case where users load these "redirects/" pages while offline. The common way to find them is by following old links from search engines, blog posts, discussion threads, etc.

If someone is still relying on these redirect files to navigate their local docs, I think the fact that the first edition links now go to the online site (just like the rustbyexample links) is clear enough without adding more clutter to the page. (We already try to de-emphasize the first edition links by making them smaller, so we clearly think most users want the new edition anyways.)

[carols10cents]

Ok, you've convinced me :) Thank you!