Re: Wrapping code in a try/except

[Andreas Röhler]

Am 19.11.2010 21:50, schrieb Andrea Crotti:
> Andreas Röhler<andreas.roehler@easy-emacs.de>  writes:
>
> >   it's not automatically
> > > indented in the rest of the C++ code...
> >
> > Write a function based on `indent-region' with reasonable defaults --
> > function-beginnning-pos, point.
> >
> > Make it run with an idle-timer like fontifying does.
> >
> > Could be a feature request if not existing already.
>
> Well in theory something like that would be perfect reading what those
> things should do:
>
> --8<---------------cut here---------------start------------->8---
> (defun re-indent-buffer ()
>    "reindent the whole buffer"
>    (indent-region yas/snippet-beg yas/snippet-end))
>
> (add-hook 'yas/after-exit-snippet-hook 're-indent-buffer)
> --8<---------------cut here---------------end--------------->8---
>
> in practice I guess there are some problems since now I have to force
> the exit of the snippet instead, so it doens't work at all...

below an example, how I would approach the issue
(must not be the best way, just for discussion...)
It takes a little bit more code.

Yasnippet seems not designed for use from programms.

;;;;

(defun my-try-wrap-function (beg end)
    (interactive "r*")
    (my-wrap-function-base beg end "try {\n" "\n} except"))

(defun my-wrap-function-base (beg end &optional before after)
  " "
  (let ((end (copy-marker end)))
    (my-wrap-function-intern beg end before after)))

(defun my-wrap-function-intern (beg end &optional before after)
  (goto-char beg)
  (when before (insert before))
  (goto-char end)
  (when after (insert after))
  (indent-region beg end)
  (beginning-of-line)
  (indent-according-to-mode))

BTW the second function might be used to cover default arguments in 
other cases like this:

  (let ((beg (cond (beg)
                   ((region-active-p)
                    (region-beginning))
                   ((bobp)
                    (point))
                   (t (defun-beginning-position))))
        (end (cond (end)
                   ((region-active-p)
                    (copy-marker (region-end)))
                   ((eobp)
                    (point))
                   (t (defun-end-position))))

 so I use this step, which might be omitted here.

happy hacking

Andreas