From: Jambunathan K <kjambunathan@gmail.com>
To: "Eric Schulte" <schulte.eric@gmail.com>
Subject: Re: [BABEL] [PROPOSAL] Seemless editing of Babel Blocks
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Date: Sun, 05 Sep 2010 14:28:16 +0530
In-Reply-To: <87r5h9czxf.fsf@gmail.com> (Eric Schulte's message of "Sat, 04
	Sep 2010 09:04:03 -0600")
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jambu> How about providing user-accessible tapping points within
jambu> 'org-babel-map-src-blocks' (or a variation thereof) that would
jambu> enable me have a custom command in my .emacs.
jambu>
jambu> For the sake of record, my suggestion is very closely related to
jambu> what is discussed here.
jambu>
jambu> http://eschulte.github.com/babel-dev/PROPOSED-tangle-entire-org-mode-file-in-comments.html

Eric> I've just pushed up an implementation of the functionality
Eric> described at the link above, see [1] for examples and details.
Eric>
Eric> Is this sufficient to satisfy the need you were addressing?  If
Eric> not how could it be improved?

Eric> Footnotes: 
Eric> [1]  http://eschulte.github.com/babel-dev/DONE-tangle-entire-org-mode-file-in-comments.html

I am making a request for an API from BABEL core which roughly parallels
org's org-map-entries.

Using this API a user should be able to 'traverse' babel and non-babel
blocks within a given scope (region, buffer), examine the local state
(say a tag or a user-defined property on a subtree), provide a verdict
on it's inclusion (yes I want it, no skip it) or possibly return a
transformed custom content (as a list).

'org-babel-map-src-blocks' has the skeletal structure for this API. All
it needs is some minimal tinkering to take on a more user-pluggable
form.

The proposed API would make UseCase-1 and UseCase-2 possible.

UseCase-1: 
http://article.gmane.org/gmane.emacs.orgmode/28823

Section-6 provides an illustration.
Section-5 helps one visualize the essentials of the propsed API.

a) org-to-org-src-view => potential consumer of the proposed API.
b) beg-org, end-org, beg-babel, end-babel => strategic 'points' of
   user-interest.
c) body, body1 => Hooks for user

UseCase-2: Tangling with custom pragmas.
http://article.gmane.org/gmane.emacs.orgmode/29805

Additional Note: Thinking out loud here (aka contrived, over-the-top
requirement). 

A user might want to override the in-buffer babel-control parameters
while tangling or execution.

Think of this scenario, I would like to tangle but with comments and
line nos as a one-off (say for circulating to my colleagues). The
in-buffer 'static/default' settings suppresses comments. I couldn't be
bothered to edit the in-buffer settings just for this one-off case. Is
there a possible way I can achieve this?

Jambunathan K.