Group list functions (AM AA etc)

[Harry Putnam <reader@newsguy.com>]

Complaint:
Seeming brokenness with Group list commands:
`A M'  does not list all matching groups from active file,
After `A A' (or g on server in server buffer) and then using `A M'
there seems to be no way to recover the full active list.  It
disappears.  None of `L', `C-u x' `A M . <RET>' or `C-x C-b'
can recover it.  

Diagnostic details:

Starting todays cvs with emacs -q -no-site-file -l ~/path.el -f gnus &
  (where path.el is nothing but the path to cvs gnus.)

cat path.el:
(add-to-list 'load-path  "/usr/local/gnus_04/lisp")
(add-to-list 'Info-default-directory-list "/usr/local/gnus_04/texi")

In group buffer press `A A' to download the full active list

Once downloaded press `A M comp\.unix' <RET>  The buffer is
immediately limited to only my *SUBSCRIBED* groups with that match.

The documentation seemingly draws a distinction between A M and A m

`A m'
     List all unread, subscribed groups with names that match a regexp
     (`gnus-group-list-matching').

`A M'
     List groups that match a regexp (`gnus-group-list-all-matching').
 
>From that I would surmise the `A M' is designed to work against `all'
groups since the keyword `subscribed' is not present.

C-h f gnus-group-list-all-matching <RET> give some confusing language
about LEVEL and LOWEST.

========================================
gnus-group-list-all-matching is an interactive compiled Lisp function
in `gnus-group'.
(gnus-group-list-all-matching LEVEL REGEXP &optional LOWEST)

List all groups that match REGEXP.
If the prefix LEVEL is non-nil, it should be a number that says which
level to cut off listing groups.
If LOWEST, don't list groups with level lower than LOWEST.

========================================

I guess this means `C-u 9  A M' should match against all and 
`C-u 1 A M' would match against only groups at level 1.

(Maybe this is a place for a clean example rather than Jargonized
programmer talk.  Since it is a common user command.)  And the info
doc doesn't mention this at all.

At any rate neither of the above do any better.  And in every usage of
`A M' the full list buffer is truncated and not recoverable by any
thing I could think of.

Thats a pretty big buffer to have to download repeatedly.  Surely
there is some way to maintain it for more than one search?  Am I just
overlooking some obvious recovery thing.

So, at least `A a' 

`A a'
     List all groups that have names that match a regexp
     (`gnus-group-apropos').

Here the behaviour is what one would expect from the description.  And
the active file buffer is left in tact.

So what is `A M' supposed to do?