python is basically up to snuff (needs more work on sessions)

lisp/org-babel-init.el

@@ -40,6 +40,7 @@
 
 ;; language specific files
 (require 'org-babel-ruby)
+(require 'org-babel-python)
 (require 'org-babel-shell)
 (require 'org-babel-lisp)
 (require 'org-babel-R)

lisp/org-babel-python.el

@@ -0,0 +1,136 @@
+;;; org-babel-python.el --- org-babel functions for python
+
+;; 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:
+
+;; Org-Babel support for evaluating python source code.
+
+;;; Code:
+(require 'org-babel)
+(require 'python)
+
+(org-babel-add-interpreter "python")
+
+(defun org-babel-execute:python (body params)
+  "Execute a block of Python code with org-babel.  This function is
+called by `org-babel-execute-src-block'."
+  (message "executing Python source code block")
+  (let* ((vars (org-babel-ref-variables params))
+         (result-params (split-string (or (cdr (assoc :results params)) "")))
+         (result-type (cond ((member "output" result-params) 'output)
+                            ((member "value" result-params) 'value)
+                            (t 'value)))
+         (full-body (concat
+                     (mapconcat ;; define any variables
+                      (lambda (pair)
+                        (format "%s=%s"
+                                (car pair)
+                                (org-babel-python-var-to-python (cdr pair))))
+                      vars "\n") "\n" body "\n")) ;; then the source block body
+         (session (org-babel-python-initiate-session (cdr (assoc :session params))))
+         (results (org-babel-python-evaluate session full-body result-type)))
+    (if (member "scalar" result-params)
+        results
+      (setq results (case result-type ;; process results based on the result-type
+                      ('output (let ((tmp-file (make-temp-file "org-babel-python")))
+                                 (with-temp-file tmp-file (insert results))
+                                 (org-babel-import-elisp-from-file tmp-file)))
+                      ('value (org-babel-python-table-or-results results))))
+      (if (and (member "vector" results) (not (listp results)))
+          (list (list results))
+        results))))
+
+(defun org-babel-python-var-to-python (var)
+  "Convert an elisp var into a string of python or python source
+code specifying a var of the same value."
+  (if (listp var)
+      (concat "[" (mapconcat #'org-babel-python-var-to-python var ", ") "]")
+    (format "%S" var)))
+
+(defun org-babel-python-table-or-results (results)
+  "If the results look like a table, then convert them into an
+Emacs-lisp table, otherwise return the results as a string."
+  (org-babel-read
+   (if (string-match "^\\[.+\\]$" results)
+       (org-babel-read
+        (replace-regexp-in-string
+         "\\[" "(" (replace-regexp-in-string
+                    "\\]" ")" (replace-regexp-in-string
+                               ", " " " (replace-regexp-in-string
+                                         "'" "\"" results)))))
+     results)))
+
+;; functions for comint evaluation
+
+(defun org-babel-python-initiate-session (&optional session)
+  "If there is not a current inferior-process-buffer in SESSION
+then create.  Return the initialized session."
+  (let ((python-buffer (or session python-buffer)))
+    (save-window-excursion (run-python nil session) (current-buffer))))
+
+(defvar org-babel-python-last-value-eval "_"
+  "When evaluated by Python this returns the return value of the last statement.")
+(defvar org-babel-python-eoe-indicator "'org_babel_python_eoe'"
+  "Used to indicate that evaluation is has completed.")
+
+(defun org-babel-python-evaluate (buffer body &optional result-type)
+  "Pass BODY to the Python process in BUFFER.  If RESULT-TYPE equals
+'output then return a list of the outputs of the statements in
+BODY, if RESULT-TYPE equals 'value then return the value of the
+last statement in BODY."
+  (org-babel-comint-in-buffer buffer
+    (let ((string-buffer "")
+          (full-body (mapconcat #'org-babel-chomp
+                                (list body org-babel-python-last-value-eval org-babel-python-eoe-indicator) "\n"))
+          results)
+      (flet ((my-filt (text) (setq string-buffer (concat string-buffer text))))
+        ;; setup filter
+        (add-hook 'comint-output-filter-functions 'my-filt)
+        ;; pass FULL-BODY to process
+        (goto-char (process-mark (get-buffer-process buffer)))
+        (insert full-body)
+        (comint-send-input)
+        ;; wait for end-of-evaluation indicator
+        (while (progn
+                 (goto-char comint-last-input-end)
+                 (not (save-excursion (and (re-search-forward comint-prompt-regexp nil t)
+                                           (re-search-forward (regexp-quote org-babel-python-eoe-indicator) nil t)))))
+          (accept-process-output (get-buffer-process buffer)))
+        ;; remove filter
+        (remove-hook 'comint-output-filter-functions 'my-filt))
+      ;; remove echo'd FULL-BODY from input
+      (if (string-match (replace-regexp-in-string "\n" "\r\n" (regexp-quote full-body)) string-buffer)
+          (setq string-buffer (substring string-buffer (match-end 0))))
+      ;; split results with `comint-prompt-regexp'
+      (setq results (cdr (member org-babel-python-eoe-indicator
+                                 (reverse (mapcar #'org-babel-trim (split-string string-buffer comint-prompt-regexp))))))
+      (org-babel-trim (case result-type
+                        (output (mapconcat #'identity (reverse (cdr results)) "\n"))
+                        (value (car results))
+                        (t (reverse results)))))))
+
+(provide 'org-babel-python)
+;;; org-babel-python.el ends here

org-babel.org

@@ -479,7 +479,6 @@ This should include...
 - sessions in comint buffers
 
 **** DONE Ruby [5/5]
-
 - [X] functional results working with comint
 - [X] script results
 - [X] ensure scalar/vector results args are taken into consideration
@@ -549,7 +548,27 @@ twoentyseven + 9
 #+resname: task-R-use-other-output
 : 28
 
-**** TODO Python
+**** TODO Python [4/5]
+- [X] functional results working with comint
+- [X] script results
+- [X] ensure scalar/vector results args are taken into consideration
+- [X] ensure callable by other source block
+- [ ] rename buffer after session
+
+#+srcname: task-new-eval-for-python
+#+begin_src python :results silent output scalar
+8
+9
+10
+#+end_src
+
+#+srcname: task-use-new-eval
+#+begin_src python :var tasking=task-new-eval-for-python() :results replace
+tasking + 2
+#+end_src
+
+#+resname: task-use-new-eval
+: 12
 
 **** TODO Shells