Re: [RFC] new :post header argument for post-processing of code block results

[Aaron Ecay <aaronecay@gmail.com>]

Hi Eric

2013ko martxoak 31an, Eric Schulte-ek idatzi zuen:
> 
> Hi,
> 
> I've been wanting to add the ability to post-process the results of a
> code block for some time, and some recent threads (e.g., [1] and [2])
> could both have benefited from post-processing of code block output.

This looks very nice!

> 
> Does this new header argument seem useful?  Any suggestions for better
> syntax which don't add too much conceptual or code complexity?

See below.

> @@ -625,6 +626,11 @@ block."
>  				      (not (listp result)))
>  				 (list (list result)) result))
>  			   (funcall cmd body params)))
> +		    ;; possibly perform post process provided its appropriate
> +		    (when (cdr (assoc :post params))
> +		      (let ((*this* result))
> +			(setq result (org-babel-ref-resolve
> +				      (cdr (assoc :post params))))))

What if you did some string surgery on the :post string, to insert
",data=\"the result\"" into the call?  That way users could just write
:post add-width(width=5cm), which would be automatically transformed
into add-width(width=5cm,data="[[graph.png]]") before being passed to
o-b-ref-resolve.

(I guess you’d have to take special care to handle things like ":post
no-args()" and ":post no-args" properly, stripping the initial comma in
the first case and adding parens in the second.)

This requires that all :post code blocks take a data
argument, but I don’t think that’s more onerous than stipulating the
*this* variable at the lisp level.

Also, I’m unclear on whether elisp is supported (or should be).  Do we
want to allow ":post (message *this*)"?

-- 
Aaron Ecay