wow wonderful! 
this works flawlessly when i select the region inside the code block and run the command. 
I wonder if any lisp wizards out there can modify Johns code and make it auto select all lines *inside* the current block and then comment it? could be useful to other people i assume.

thx again



On Sat, Jun 27, 2015 at 2:32 PM, John Kitchin <jkitchin@andrew.cmu.edu> wrote:
This seems to work for some toy examples:

(defun comment-org-in-src-block ()
 (interactive)
 (org-edit-special)
 (comment-dwim nil)
 (org-edit-src-exit))


Xebar Saram writes:

> Hi all
>
> i was wondering if anyone knew of a command or bind to quickly comment the
> entire content of an org code block (with the correct comment syntax)?
>
> thx!
>
> Z

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