;;; org-babel-table.el --- integration for calling org-babel functions from tables

;; Copyright (C) 2009 Eric Schulte

;; Author: Eric Schulte
;; Keywords: literate programming, reproducible research
;; Homepage: http://orgmode.org
;; Version: 0.01

;;; License:

;; This program is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation; either version 3, or (at your option)
;; any later version.
;;
;; This program is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.
;;
;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs; see the file COPYING.  If not, write to the
;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
;; Boston, MA 02110-1301, USA.

;;; Commentary:

;; Should allow calling functions from org-mode tables using the
;; function `sbe' as so...
;; 
;; #+begin_src emacs-lisp :results silent
;; (defun fibbd (n) (if (< n 2) 1 (+ (fibbd (- n 1)) (fibbd (- n 2)))))
;; #+end_src
;; 
;; #+srcname: fibbd
;; #+begin_src emacs-lisp :var n=2 :results silent
;; (fibbd n)
;; #+end_src
;; 
;; | original | fibbd  |
;; |----------+--------|
;; |        0 |        |
;; |        1 |        |
;; |        2 |        |
;; |        3 |        |
;; |        4 |        |
;; |        5 |        |
;; |        6 |        |
;; |        7 |        |
;; |        8 |        |
;; |        9 |        |
;; #+TBLFM: $2='(sbe 'fibbd (n $1))

;;; Code:
(require 'org-babel)

(defun org-babel-table-truncate-at-newline (string)
  (if (and (stringp string) (string-match "[\n\r]" string))
      (concat (substring string 0 (match-beginning 0)) "...")
    string))

(defmacro sbe (source-block &rest variables)
  "Return the results of calling SOURCE-BLOCK with all assigning
every variable in VARIABLES.  Each element of VARIABLES should be
a two element list, whose first element is the name of the
variable and second element is a string of its value.  The
following call to `sbe' would be equivalent to the following
source code block.

 (sbe 'source-block (n 2) (m 3))

#+begin_src emacs-lisp :var results=source-block(n=2, m=3) :results silent
results
#+end_src"
  (unless (stringp source-block) (setq source-block (symbol-name source-block)))
  (org-babel-table-truncate-at-newline ;; org-table cells can't be multi-line
   (if (and source-block (> (length source-block) 0))
       (let ((params
	      (eval `(org-babel-parse-header-arguments
		      (concat ":var results="
			      ,source-block
			      "("
			      (mapconcat (lambda (var-spec)
					   (format "%S=%s" (first var-spec) (second var-spec)))
					 ',variables ", ")
			      ")")))))
         (org-babel-execute-src-block t (list "emacs-lisp" "results" params)))
     "")))

(provide 'org-babel-table)
;;; org-babel-table.el ends here