[Users] Understanding processing (and pre/post-)

[Jim Pachowski]

> I understand that pre-processing rules run before processing ones and
> post-processing ones after. However it is unclear to me what is the
> purpose of having pre and post at all.

Mainly for organisation & ease.

> In other words: Why only processing itself may be insufficient
> and in what situations could one benefit by having the additional
> functionality of pre/post-processing?

Pre & Post run on every folder, every time you open a folder.

Folder processing only runs on that specific folder.

Example 1: I want all my emails that I have replied to, moved to my
"Archive" folder.
Option 1: I set up that processing rule in ALL folders individually.
Option 2: I set up a pre or post-processing rule. Voila!

Example 2: I want all emails addressed to me that I have not replied
to, marked in orange when they are 2 days old, red when they are 4
days old.
Option 1: I set up that processing rule in ALL folders individually.
Option 2: I set up a pre or post-processing rule. Voila!

Now you will wonder what is the point in having pre AND post if either
can be used. Well, those were basic examples. Here is something based
on what I use (my rules are more complex):

Example 3 [ADVANCED]: All emails with me in TO or CC, not replied to,
older than 2 days marked red & set flag (makes navigation easy), but
for claws-mailing list, only older than 5 days marked red & flagged,
and any red that are replied to anywhere, set to normal & moved to my
archive folder segregated by quarters (18q1, 18q2, etc.).
pre-processing (all folders): to or CC has me and age is more than 2
that I have not replied yet, mark it red & set flag
claws-mailing list only processing: red and age less than 5, clear red & flag.
post-processing (all folders): red & replied to, clear red & flag,
then move to current archive (one place sets target for ALL folders).

Now while you may question me on why I do mail like that, the fact is
that I do and the bigger fact is that tthere is no way that level of
complexity can be achieved sanely and in so few steps across my entire
folder tree without pre-folder-post processing.

- JP