Re: functions to download mailing list archives

[Óscar Fuentes]

GH <project@gnuhacker.org> writes:

> so Im writing functions to interact with ~lists.gnu.org~ http interfaces
>
> For example this function to download lists mbox archives:

[snip]

> But sadly the recursion stop with this warning:
>
> file-local-name: Lisp nesting exceeds `max-lisp-eval-depth'
>
> any idea to fix?

Instead of a recursive function use a recursive data structure: a list.

The outer function puts in the list the initial URL, and then, in a
loop, pops from the list a URL, downloads it, adds to the list the
referenced URLs and repeats until the list is empty or some other
condition is met.

Some complications may remain: for instance, you need to detect cycles
(the failure on your posted code probably comes from that). A list also
comes handy for that, if you walk the list with dolist instead of
popping elements and add new ones with add-to-list, which omits elements
which are already in the list.