Disabling automatic reindentation of the current line after a newline

[Jean Abou Samra <jean@abou-samra.fr>]

Hi,

Suppose I am in Lisp mode and I write this:

(defun f (x)
          (g x))

Note the extra spaces compared to standard indentation. If, after
writing the last parenthesis, I press RET, Emacs automatically
reindents the second line, changing the code to this:

(defun f (x)
  (g x))


The same happens with other major modes.

I am aware that I can turn this off with M-x electric-indent-mode.
However, that also disables any automatic indentation for the next
line when I press RET. What I'd like is for Emacs to auto-insert
the number of spaces it deems necessary for the new, still blank
line whenever I press RET, without also reindenting the previous
line, where I might have changed the indentation if Emacs made
a mistake (e.g., if the major mode I am using is not 100% accurate,
or if I have a slightly different style for which no option exists
in that mode).

Is this possible?

Thanks,
Jean