Tentative patch to keep org-babel-results-keyword when calling org-babel-remove-result

[Daniele Pizzolli <dan@toel.it>]

Hello @ll,

this is my fist post on the list.  Thanks to everybody for posting
interesting things and keeping org-mode improving!

I am seeking help because of my limited elisp knowledge.

This is my incomplete patch to extend org-babel-remove-result to keep
the org-babel-results-keyword when removing the results.

I need to keep the org-babel-results-keyword because I want to commit
to my dvcs a clean file and easily evaluate the results at any time
later.

Unfortunately running org-babel-remove-result on a snippet like the
following:

#+BEGIN_SRC octave :results value file
% at the end produce an image
#+END_SRC

#+ATTR_LATEX: :width 3cm
#+RESULTS:
[[file:image_01.png]]

Will output:

#+BEGIN_SRC octave :results value file
% at the end produce an image
#+END_SRC

#+ATTR_LATEX: :width 3cm

And a run of org-babel-execute-buffer will produce:

#+BEGIN_SRC octave :results value file
% at the end produce an image
#+END_SRC

#+RESULTS:
[[file:image_01.png]]

#+ATTR_LATEX: :width 3cm

changing the position of the LaTeX specific attribute #+ATTR_LATEX: in
way that it becomes useless.

The patch add an optional argument to org-babel-remove-result but
relies to an hard-coded value of the length of the default
org-babel-results-keyword plus syntax elements: "#+RESULTS:".

Instead of calculating lengths I think that is better to move to next
line.

I also skipped a deletion of the last char assuming that is always a
new line.  Is this assumption correct?  If we delete the last line
we can end with:

#+RESULTS:
** some other section

That will cause problem in the next evaluation.

I will appreciate your suggestions to improve the patch myself.  It
would be great also if anybody can implement it properly and get it merged.

Thanks in advance,
Daniele Pizzolli


diff --git a/lisp/ob-core.el b/lisp/ob-core.el
index cc6b7a9..7517ebf 100644
--- a/lisp/ob-core.el
+++ b/lisp/ob-core.el
@@ -2159,15 +2159,18 @@ code ---- the results are extracted in the syntax of the source
  	  (set-marker visible-beg nil)
  	  (set-marker visible-end nil))))))

-(defun org-babel-remove-result (&optional info)
-  "Remove the result of the current source block."
+(defun org-babel-remove-result (&optional info keep-keyword)
+  "Remove the result of the current source block.  Optionally
+keep the result keyword."
    (interactive)
    (let ((location (org-babel-where-is-src-block-result nil info)) start)
      (when location
-      (setq start (- location 1))
+      (setq start (if keep-keyword (+ location 10) (- location 1)))
        (save-excursion
          (goto-char location) (forward-line 1)
-        (delete-region start (org-babel-result-end))))))
+        (delete-region
+	  start
+          (if keep-keyword (- (org-babel-result-end) 1) (org-babel-result-end)))))))