Re: The function prin1 prints "..." at the end of a long list.

[John Paul Wallington <jpw@gnu.org>]

Matthieu Moy <Matthieu.Moy@st.com> wrote:

>>> The  function  prin1  sometimes  truncates  the end  of  a  long  list
>>> (auto-mode-alist is a good example of such list):
>> [This corrupts my SCORE file in Gnus]
>>> Now,  more fun  :  I launch  another  Emacs session,  and  in the  new
>>> session, everything works as expected : C-h v auto-mode-alist shows me
>>> the full value,  and so on. The problem seems  to happen randomly, but
>>> when it happens  once, then, it will continue to  happen until the end
>>> of the session.
>>> 
>>> I have the same problem on a Solaris box and a Linux (Debian 3.0) box,
>>> both with Emacs 21.2. 
>>
>> What is the value of `print-length' in the misbehaving session?  Maybe
>> some code set rather than bound it to a non-nil value.
>
> Yep, that's  it. The  value is  10 in a  buggy session,  and nil  in a
> "sane" session. 
[...]
> So, it seems to me that there are actually 2 bugs :
>
> * Something has set my print-level  without my asking for it. This may
>   be  a  Gnus  bug or  an  Emacs  bug.  (Or  something obscure  in  my
>   configuration, but grep doesn't agree on that ...)

On cursory examination I don't see how it would be set rather than
bound by Emacs sources, or where it would get the value 10.  Have you
customized `eval-expression-print-length' or loaded the cust-print
library?  Perhaps it is set by the debugger/edebug ?

> * The dump of  the SCORE file does is  not protected against incorrect
>   print-length. This is a Gnus bug.

You have suggested a patch to the Gnus maintainers, so this aspect of
your bug will fixed by them, I guess.