Re: Automatic smart indentation

[Kevin Rodgers <ihs_4664@yahoo.com>]

Martin Stone Davis wrote:

> I've read the threads in this list pertaining to indentation, but I 
> haven't found a solution to the following problem:  While editing a lisp 
> program, I want to keep the indentation "correct" at all times.
> 
> i.e. If I yank I want to reindent. If I delete a ), I want it to 
> reindent, If I insert a (, change the name of a function from if to 
> when, undo etc. etc. etc., I want to reindent.
> 
> The solution I came up with is:
> 
> (setq lisp-indent-function 'common-lisp-indent-function)
> (add-hook 'after-change-functions
>        (lambda (start end pre-change-length)
>              (indent-region start (buffer-size) nil)))
> 
> The problem is that it somehow gets into an endless loop *sometimes* 
> when I undo.  It might have problems in other situations, but that's 
> whet I've found so far.

Sorry, I can't help you with that.  But I can tell you that (buffer-size)
should almost certainly be (point-max).  And you might want to add a check
for (eq major-mode 'lisp-mode), or make after-change-functions a local hook
variable in Lisp mode buffers (by putting the add-hook in a lisp-mode-hook
function, and specifying the optional LOCAL arg).

You might also have better luck if you call indent-region with a region
that starts at the beginning of the line:
(save-excursion (goto-char start) (line-beginning-position))

-- 
Kevin Rodgers