newline-and-indent vs. electric-indent-mode

[haj@posteo.de (Harald Jörg)]

Hi all,

in a debugging session for some indenting bugs I noticed with some
surprise how often the mode-specific indenting function is called.
There seems to be a systematic overlap between the keybinding of RET and
electric-indent-mode.

Many (almost all?) modes bind RET to newline-and-indent, but '(?\n) is
also the default value of electric-indent-chars.  So, whenever a newline
is entered, there are three calls to the mode-specific indenting
function:

 - one call for the current line, caused by electric-indent-mode.  This
   makes some sense because the line's content might suggest a different
   indentation than what could be guessed when the line started out as a
   new empty line.  It is annoying, however, when the mode gets the
   indentation wrong (which occasionally happens).  It is also
   superfluous if the character which causes a change in indentation
   (for example "}") is either itself in electric-indent-chars (as in
   perl-mode) or handled by the mode's keymap (as in cperl-mode), both
   resulting in a call to the indenting function.

 - two calls for the following, empty line.  One is caused by '(?\n)
   being in electric-indent-chars, the other by the current command
   being newline-AND-INDENT.  This doesn't make any sense.

Should electric-indent-mode be switched off by modes which map RET to
newline-and-indent? Or should the modes refrain from mapping RET?
-- 
Cheers,
haj