Re: Visual cleanup for customize buffers

[Luc Teirlinck]

       - Don't show the "Hide value" button for trivial values which
         fit on one line initially.  I don't see ANY reason why a
         user would click on that button to, say, hide a boolean
         or numeric value.

   That seems ok to me, provided the problem Luc is concerned about
   is not a real problem.

Now I have some additional concerns which are definitely real problems.
This is not the type of change that should be attempted shortly (one
can always hope) before a release and maybe even never.  It might look
small and harmless at first view but it definitely is not.

I installed Kim's two patches.  Somehow, after that _all_ options
started out hidden.  I believe that _must_ be due to the fact that I
did something wrong.

However, I believe that the following bug is definitely real and not
due to some bad application of patches (I guessed this bug would occur
from reading the code).  Evaluate:

(defcustom long-var
  
"1111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111"
  "Great doc."
  :group 'help-at-pt
  :type 'string)

Do `M-x customize-group RET help-at-pt'.

With or without Kim's patch this option starts out hidden.  Without
Kim's patch, if I unhide it, I can hide it again, as I clearly should
be able to do.  With Kim's patch, there is no button to hide it.

Kim uses a different criterion for putting in a Show/Hide button than
Custom does.  This obviously leads to bugs.  Even if Kim somehow
managed to use exactly the same criteria as Custom does (which seem to
be not completely trivial and spread out over the code), we would keep
the following two problems (as well as others):

1.  The criteria Custom uses are heuristic and occasionally may show
    very long values that the user _definitely_ may want to hide.

2.  There would be the continuous danger of the two conditions getting
    out of sync at any moment whatsoever, leading to very annoying bugs.

Sincerely,

Luc.