lisp/ob-table.el

   1 ;;; ob-table.el --- support for calling org-babel functions from tables
   2
   3 ;; Copyright (C) 2009-2014 Free Software Foundation, Inc.
   4
   5 ;; Author: Eric Schulte
   6 ;; Keywords: literate programming, reproducible research
   7 ;; Homepage: http://orgmode.org
   8
   9 ;; This file is part of GNU Emacs.
  10
  11 ;; GNU Emacs is free software: you can redistribute it and/or modify
  12 ;; it under the terms of the GNU General Public License as published by
  13 ;; the Free Software Foundation, either version 3 of the License, or
  14 ;; (at your option) any later version.
  15
  16 ;; GNU Emacs is distributed in the hope that it will be useful,
  17 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 ;; GNU General Public License for more details.
  20
  21 ;; You should have received a copy of the GNU General Public License
  22 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  23
  24 ;;; Commentary:
  25
  26 ;; Should allow calling functions from org-mode tables using the
  27 ;; function `org-sbe' as so...
  28
  29 ;; #+begin_src emacs-lisp :results silent
  30 ;;   (defun fibbd (n) (if (< n 2) 1 (+ (fibbd (- n 1)) (fibbd (- n 2)))))
  31 ;; #+end_src
  32
  33 ;; #+name: fibbd
  34 ;; #+begin_src emacs-lisp :var n=2 :results silent
  35 ;; (fibbd n)
  36 ;; #+end_src
  37
  38 ;; | original | fibbd  |
  39 ;; |----------+--------|
  40 ;; |        0 |        |
  41 ;; |        1 |        |
  42 ;; |        2 |        |
  43 ;; |        3 |        |
  44 ;; |        4 |        |
  45 ;; |        5 |        |
  46 ;; |        6 |        |
  47 ;; |        7 |        |
  48 ;; |        8 |        |
  49 ;; |        9 |        |
  50 ;; #+TBLFM: $2='(org-sbe 'fibbd (n $1))
  51
  52 ;;; Code:
  53 (require 'ob-core)
  54
  55 (defun org-babel-table-truncate-at-newline (string)
  56   "Replace newline character with ellipses.
  57 If STRING ends in a newline character, then remove the newline
  58 character and replace it with ellipses."
  59   (if (and (stringp string) (string-match "[\n\r]\\(.\\)?" string))
  60       (concat (substring string 0 (match-beginning 0))
  61               (if (match-string 1 string) "...")) string))
  62
  63 (defmacro org-sbe (source-block &rest variables)
  64   "Return the results of calling SOURCE-BLOCK with VARIABLES.
  65
  66 Each element of VARIABLES should be a list of two elements: the
  67 first element is the name of the variable and second element is a
  68 string of its value.
  69
  70 So this `org-sbe' construct
  71
  72  (org-sbe 'source-block (n $2) (m 3))
  73
  74 is the equivalent of the following source code block:
  75
  76  #+begin_src emacs-lisp :var results=source-block(n=val_at_col_2, m=3) :results silent
  77  results
  78  #+end_src
  79
  80 NOTE: By default, string variable names are interpreted as
  81 references to source-code blocks, to force interpretation of a
  82 cell's value as a string, prefix the identifier a \"$\" (e.g.,
  83 \"$$2\" instead of \"$2\" or \"$@2$2\" instead of \"@2$2\").
  84
  85 NOTE: It is also possible to pass header arguments to the code
  86 block.  In this case a table cell should hold the string value of
  87 the header argument which can then be passed before all variables
  88 as shown in the example below.
  89
  90 | 1 | 2 | :file nothing.png | nothing.png |
  91 #+TBLFM: @1$4='(org-sbe test-sbe $3 (x $1) (y $2))"
  92   (declare (debug (form form)))
  93   (let* ((header-args (if (stringp (car variables)) (car variables) ""))
  94          (variables (if (stringp (car variables)) (cdr variables) variables)))
  95     (let* (quote
  96            (variables
  97             (mapcar
  98              (lambda (var)
  99                ;; ensure that all cells prefixed with $'s are strings
 100                (cons (car var)
 101                      (delq nil (mapcar
 102                                 (lambda (el)
 103                                   (if (eq '$ el)
 104                                       (prog1 nil (setq quote t))
 105                                     (prog1
 106                                         (cond
 107                                          (quote (format "\"%s\"" el))
 108                                          ((stringp el) (org-no-properties el))
 109                                          (t el))
 110                                       (setq quote nil))))
 111                                 (cdr var)))))
 112              variables)))
 113       (unless (stringp source-block)
 114         (setq source-block (symbol-name source-block)))
 115       (let ((result
 116              (if (and source-block (> (length source-block) 0))
 117                  (let ((params
 118                         ;; FIXME: Why `eval'?!?!?
 119                         (eval `(org-babel-parse-header-arguments
 120                                 (concat
 121                                  ":var results="
 122                                  ,source-block
 123                                  "[" ,header-args "]"
 124                                  "("
 125                                  (mapconcat
 126                                   (lambda (var-spec)
 127                                     (if (> (length (cdr var-spec)) 1)
 128                                         (format "%S='%S"
 129                                                 (car var-spec)
 130                                                 (mapcar #'read (cdr var-spec)))
 131                                       (format "%S=%s"
 132                                               (car var-spec) (cadr var-spec))))
 133                                   ',variables ", ")
 134                                  ")")))))
 135                    (org-babel-execute-src-block
 136                     nil (list "emacs-lisp" "results" params)
 137                     '((:results . "silent"))))
 138                "")))
 139         (org-babel-trim (if (stringp result) result (format "%S" result)))))))
 140
 141 (provide 'ob-table)
 142
 143
 144
 145 ;;; ob-table.el ends here