lisp/org/ob-js.el

   1 ;;; ob-js.el --- org-babel functions for Javascript
   2
   3 ;; Copyright (C) 2010-2011 Free Software Foundation
   4
   5 ;; Author: Eric Schulte
   6 ;; Keywords: literate programming, reproducible research, js
   7 ;; Homepage: http://orgmode.org
   8 ;; Version: 7.4
   9
  10 ;;; License:
  11
  12 ;; This program is free software; you can redistribute it and/or modify
  13 ;; it under the terms of the GNU General Public License as published by
  14 ;; the Free Software Foundation; either version 3, or (at your option)
  15 ;; any later version.
  16 ;;
  17 ;; This program is distributed in the hope that it will be useful,
  18 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 ;; GNU General Public License for more details.
  21 ;;
  22 ;; You should have received a copy of the GNU General Public License
  23 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  24 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  25 ;; Boston, MA 02110-1301, USA.
  26
  27 ;;; Commentary:
  28
  29 ;; Now working with SBCL for both session and external evaluation.
  30 ;;
  31 ;; This certainly isn't optimally robust, but it seems to be working
  32 ;; for the basic use cases.
  33
  34 ;;; Requirements:
  35
  36 ;; - a non-browser javascript engine such as node.js http://nodejs.org/
  37 ;;   or mozrepl http://wiki.github.com/bard/mozrepl/
  38 ;;
  39 ;; - for session based evaluation mozrepl and moz.el are required see
  40 ;;   http://wiki.github.com/bard/mozrepl/emacs-integration for
  41 ;;   configuration instructions
  42
  43 ;;; Code:
  44 (require 'ob)
  45 (require 'ob-ref)
  46 (require 'ob-comint)
  47 (require 'ob-eval)
  48 (eval-when-compile (require 'cl))
  49
  50 (declare-function run-mozilla "ext:moz" (arg))
  51
  52 (defvar org-babel-default-header-args:js '()
  53   "Default header arguments for js code blocks.")
  54
  55 (defvar org-babel-js-eoe "org-babel-js-eoe"
  56   "String to indicate that evaluation has completed.")
  57
  58 (defcustom org-babel-js-cmd "node"
  59   "Name of command used to evaluate js blocks."
  60   :group 'org-babel
  61   :type 'string)
  62
  63 (defvar org-babel-js-function-wrapper
  64   "require('sys').print(require('sys').inspect(function(){%s}()));"
  65   "Javascript code to print value of body.")
  66
  67 (defun org-babel-execute:js (body params)
  68   "Execute a block of Javascript code with org-babel.
  69 This function is called by `org-babel-execute-src-block'"
  70   (let* ((org-babel-js-cmd (or (cdr (assoc :cmd params)) org-babel-js-cmd))
  71          (result-type (cdr (assoc :result-type params)))
  72          (full-body (org-babel-expand-body:generic
  73                      body params (org-babel-variable-assignments:js params))))
  74     (org-babel-js-read
  75      (if (not (string= (cdr (assoc :session params)) "none"))
  76          ;; session evaluation
  77          (let ((session (org-babel-prep-session:js
  78                          (cdr (assoc :session params)) params)))
  79            (nth 1
  80                 (org-babel-comint-with-output
  81                     (session (format "%S" org-babel-js-eoe) t body)
  82                   (mapc
  83                    (lambda (line)
  84                      (insert (org-babel-chomp line)) (comint-send-input nil t))
  85                    (list body (format "%S" org-babel-js-eoe))))))
  86        ;; external evaluation
  87        (let ((script-file (org-babel-temp-file "js-script-")))
  88          (with-temp-file script-file
  89            (insert
  90             ;; return the value or the output
  91             (if (string= result-type "value")
  92                 (format org-babel-js-function-wrapper full-body)
  93               full-body)))
  94          (org-babel-eval
  95           (format "%s %s" org-babel-js-cmd
  96                   (org-babel-process-file-name script-file)) ""))))))
  97
  98 (defun org-babel-js-read (results)
  99   "Convert RESULTS into an appropriate elisp value.
 100 If RESULTS look like a table, then convert them into an
 101 Emacs-lisp table, otherwise return the results as a string."
 102   (org-babel-read
 103    (if (and (stringp results) (string-match "^\\[.+\\]$" results))
 104        (org-babel-read
 105         (concat "'"
 106                 (replace-regexp-in-string
 107                  "\\[" "(" (replace-regexp-in-string
 108                             "\\]" ")" (replace-regexp-in-string
 109                                        ", " " " (replace-regexp-in-string
 110                                                  "'" "\"" results))))))
 111      results)))
 112
 113 (defun org-babel-js-var-to-js (var)
 114   "Convert VAR into a js variable.
 115 Convert an elisp value into a string of js source code
 116 specifying a variable of the same value."
 117   (if (listp var)
 118       (concat "[" (mapconcat #'org-babel-js-var-to-js var ", ") "]")
 119     (format "%S" var)))
 120
 121 (defun org-babel-prep-session:js (session params)
 122   "Prepare SESSION according to the header arguments specified in PARAMS."
 123   (let* ((session (org-babel-js-initiate-session session))
 124          (var-lines (org-babel-variable-assignments:js params)))
 125     (when session
 126       (org-babel-comint-in-buffer session
 127         (sit-for .5) (goto-char (point-max))
 128         (mapc (lambda (var)
 129                 (insert var) (comint-send-input nil t)
 130                 (org-babel-comint-wait-for-output session)
 131                 (sit-for .1) (goto-char (point-max))) var-lines)))
 132     session))
 133
 134 (defun org-babel-variable-assignments:js (params)
 135   "Return list of Javascript statements assigning the block's variables"
 136   (mapcar
 137    (lambda (pair) (format "var %s=%s;"
 138                           (car pair) (org-babel-js-var-to-js (cdr pair))))
 139    (mapcar #'cdr (org-babel-get-header params :var))))
 140
 141 (defun org-babel-js-initiate-session (&optional session)
 142   "If there is not a current inferior-process-buffer in SESSION
 143 then create.  Return the initialized session."
 144   (unless (string= session "none")
 145     (cond
 146      ((string= "mozrepl" org-babel-js-cmd)
 147       (require 'moz)
 148       (let ((session-buffer (save-window-excursion
 149                               (run-mozilla nil)
 150                               (rename-buffer session)
 151                               (current-buffer))))
 152         (if (org-babel-comint-buffer-livep session-buffer)
 153             (progn (sit-for .25) session-buffer)
 154           (sit-for .5)
 155           (org-babel-js-initiate-session session))))
 156      ((string= "node" org-babel-js-cmd )
 157       (error "session evaluation with node.js is not supported"))
 158      (t
 159       (error "sessions are only supported with mozrepl add \":cmd mozrepl\"")))))
 160
 161 (provide 'ob-js)
 162
 163
 164 ;;; ob-js.el ends here