On Mon, 05 Mar 2012 06:21:52 +0400, Dmitry Kurochkin <dmitry.kurochkin@gmail.com> wrote:
> On Thu,  1 Mar 2012 21:24:38 +0100, Daniel Schoepe <daniel@schoepe.org> wrote:
> > notmuch-saved-search-sort-function might destructively modify its
> > input (`sort' does that, for instance), so it should not be given
> > notmuch-saved-searches directly.
> > ---
> 
> -1
> 
> I think we should require `notmuch-saved-search-sort-function' not to
> have side effects.  Current documentation should be more clear about
> this.  We need to fix `notmuch-sort-saved-searches' to copy the list
> before calling `sort'.  But we should not do it in
> `notmuch-hello-insert-saved-searches' for any sorting function (which
> may not need this copying).

My reasoning was that since sort is such a common function, many users
will probably use sort for their own sorting functions, not realizing
that it has side effects. This will lead to confusing behavior that's
not so easy to track down.

Copying the list of saved searches when running notmuch-hello does not
seem be relevant to performance to me, since it's a) not called that
often and b) the list of saved searches will rarely exceed 30 elements.

Hence, this way we can avoid some headaches for users who define their
own sorting functions at a negligible (performance) cost. Incidentally,
this is also how notmuch-hello did it before the user-defined sections
patches.

Cheers,
Daniel