folded group view

[lee <lee@yun.yagibdah.de>]

Hi,

is it possible to have a "folded" group view? I´ll give an example to
explain what I mean: Let´s say you have the following groups shown in
your group buffer:


bogus
mail.example.good
mail.misc.abc
mail.misc.def
mail.misc.afiaf
mail.misc.asfafmmf
mail.test.local
mail.test.remote
some.other.example.asdfasf
some.other.example.more


That´s an "unfolded" display. With a "folded" display, it would look
like this:


bogus
mail.*
some.*


Now go to the line that shows "mail.*" and unfold the next level of
it. You´d see:


bogus
--------------
mail.example.good
mail.misc.*
mail.test.*
--------------
some.*


Note that it intentionally shows "mail.example.good" instead of
"mail.example.*". If there was also "mail.example.bad", it would show
"mail.example.*", of course. When you unfold "mail.misc.*", you get:


bogus
mail.example.good
--------------
mail.misc.abc
mail.misc.def
mail.misc.afiaf
mail.misc.asfafmmf
--------------
mail.test.*
--------------
some.*


Optionally, all the groups not unfolded could be exempt from being
displayed, so having unfolded two levels of "mail.*", you´d only see it
as a "current hierarchy":


--------------
mail.misc.abc
mail.misc.def
mail.misc.afiaf
mail.misc.asfafmmf
--------------


Some settings about folding could be specified as group-parameters, so
that hierachies can be exempt from being folded and users can specify
what seperator to use. When searching for group names, the groups hidden
in the fold should still be found: think of org-mode ... The seperating
lines are to indicate that either a hierarchy is unfolded or that only
the current hierachy is displayed. Another idea that comes to mind is
"reverse folding" and "partial folding": Reverse folding would operate
with the group names reversed, like "abc.misc.mail" instead of
"mail.misc.abc".

Partial folding would allow you to use arbitrary parts of group names to
fold them on, either specified as windcard strings, or as levels of
hierarchy: If you´d set your partial folding specifier to ".*example.*",
you´d see:


bogus
mail.misc.abc
mail.misc.def
mail.misc.afiaf
mail.misc.asfafmmf
mail.test.local
mail.test.remote
--------------
*.example.*


If you´d set the partial folding specifier to 3, you´d get:


bogus
--------------
mail.example.good
mail.misc.*
some.other.*
some.other.*


Is there anything like this already built in? If not, please consider it
a feature request :)