[Orgmode] [BABEL] Seemless editing of Babel Blocks

[Jambunathan K]

I am presenting a code snippet that would make editing of babel blocks
quite seemless. The editor parallels (inline!) editing of table
blocks. A suitable variation thereof could be considered for inclusion
in the core distribution.

Few other suggestions:
1. While invoking babel editor, offer babel guard lines as comment
   blocks in the native mode.
   
2. On saving code blocks, do the reverse.
   
For example, in case of emacs-lisp
   
#+begin_src emacs_lisp:
(message "Hello World")
#+end_src

could be offered as:

;; begin_src emacs_lisp:
(message "Hello World")
;; end_src

One could then add say a ':tangle ...' directive and have it persisted
as 

#+begin_src emacs_lisp: :tangle HelloWorld.el
(message "Hello World")
#+end_src

2. Is it possible to do org-edit-src-exit with more 'natural'
   keybinding like C-x C-w or C-x C-s. Furthermore, C-x C-w could fix
   up '#+srcname: ' directive as well.

   
;; CODE SNIPPET   

;; make org-cycle look for babel blocks
((org-at-babel-p)
 (call-interactively 'org-edit-special))

;; A semicolon followed by <TAB> would invoke the babel editor.
;; A tab within the babel block would invoke the babel editor.

(defconst org-babel-invoke-editor-regexp "^[ \t]*\\(;\\)"
  "Detect beginning of babel src code")

(defun org-at-babel-p () 
  ""
  (beginning-of-line 1)

  (cond 
   ((looking-at org-babel-invoke-editor-regexp)
    (unless  (org-babel-where-is-src-block-head)
      (insert  "#+begin_src emacs-lisp :\n\n")
        
      (insert  "#+end_src")
      (kill-line)
      (forward-line  -1)
      t)
    )

   ((org-babel-where-is-src-block-head) t)
   (t nil)
   )
  )