Re: [Lynx-dev] V-page. Comp-Sci question: "jumping back in" via V-page: coroutine, continuation, what?

[Paul B. Mahol]

On 3/27/08, David Combs <address@hidden> wrote:
> Question: how to get back to where I was, ie where the *first* h had
> returned me to (from reading an article)?
>
> Currently, I believe, there's no way to get back into truthout,
> *cursor at same point that first h got me to" -- before being
> popped off a presumed stack (hmmm -- I wonder just how that
> v-page algorithm works, what data-structure, etc).
>
It is defined in src/LYHistory.c
> Rather, I must again "click" (ie, hit <return>) the truthout-link,
> and I end up at the top of truthout, now down where I had been
> before my extra h.
>
> QUESTION: What would it take to be able to do just that, ie
> get back to exactly where I had been?
>
In recent lynx, you could use Ctrl+u (NEXT_DOC) to undo recent h (PREV_DOC). 
But it works only in active branch of tree (only through history list) and not 
inside Visited links page ie. it is somehow completly different from how it is 
done in other browsers.
And that is mainly because they dont do any difference from History and Visited 
links - that is same thing for them.
> QUESTION: Looking at the V-page "tree", what would it take
> to be able go directly to any of those V-page nodes,
> landing there with the cursor at where it had been when I
> had last been there?
In recent lynx there is (*some kind of*) sessions support, and if you ever 
tried that feature, and after that looked at session file you will notice that 
lines started with h (history entries) have always 2 numbers; that is what are 
you looking for; first number is rendered document line and second one is 
active link. (Rendered document active line depends on terminal size - so it 
can be different - and completely broken after you change terminal size betwen 
sesions or during current session ...)
On other hand *Visited Links code* doesnt store last active link and line.
> Hmmm. We already do have the V-page data structure, whatever
> it is, that shows the path we had been on when we first
> hit a node (site). And if we "click" on it, we'll end up
> at the *top* of that page.
>
> What would we have to save in that V-graph or whatever it is,
> just the number (the square-bracketed numerical label of
> the link) we were last at?
It is possible and simple to add.
> And what about after getting back there, we hit h,
> what happens? Do we go to the father-node as shown in the
> V-page?
PREV_DOC and NEXT_DOC will take in account line and link number stored in 
history list - so cursor will be positioned on last link as it was before last 
visit. Note that *Visited Links* list doesnt have nothing with *History* list 
they are completely different.
> Anyway, interesting questions, with maybe not-so-difficult
> solutions. (Not that I's asking for Lynx to have this
> ability -- although it would be useful!)
Could this be enabled by default or via some kind of runtime option?
> Thanks for reading this far!
>
Thank you for nice idea!