org-babel: Add support for perl

Session-based evaluation is not supported.

contrib/babel/lisp/langs/org-babel-perl.el

@@ -0,0 +1,122 @@
+;;; org-babel-perl.el --- org-babel functions for perl evaluation
+
+;; Copyright (C) 2009 Dan Davison, Eric Schulte
+
+;; Author: Dan Davison, 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 perl source code.
+
+;;; Code:
+(require 'org-babel)
+
+(org-babel-add-interpreter "perl")
+
+(add-to-list 'org-babel-tangle-langs '("perl" "pl" "#!/usr/bin/env perl"))
+
+(defun org-babel-execute:perl (body params)
+  "Execute a block of Perl code with org-babel.  This function is
+called by `org-babel-execute-src-block' via multiple-value-bind."
+  (message "executing Perl source code block")
+  (let ((full-body (concat
+		    (mapconcat ;; define any variables
+		     (lambda (pair)
+		       (format "$%s=%s;"
+			       (car pair)
+			       (org-babel-perl-var-to-perl (cdr pair))))
+		     vars "\n") "\n" (org-babel-trim body) "\n")) ;; then the source block body
+	(session (org-babel-perl-initiate-session session)))
+    (org-babel-perl-evaluate session full-body result-type)))
+
+(defun org-babel-prep-session:perl (session params)
+  "Prepare SESSION according to the header arguments specified in PARAMS."
+  (error "Sessions are not supported for Perl."))
+
+;; helper functions
+
+(defun org-babel-perl-var-to-perl (var)
+  "Convert an elisp var into a string of perl source code
+specifying a var of the same value."
+  (if (listp var)
+      (concat "[" (mapconcat #'org-babel-perl-var-to-perl var ", ") "]")
+    (format "%S" var)))
+
+(defvar org-babel-perl-buffers '(:default . nil))
+
+(defun org-babel-perl-initiate-session (&optional session)
+  "Simply return nil, as sessions are not supported by perl"
+nil)
+
+(defvar org-babel-perl-wrapper-method
+  "
+sub main {
+%s
+}
+@r = main;
+open(o, \">%s\");
+print o join(\"\\n\", @r), \"\\n\"")
+
+(defvar org-babel-perl-pp-wrapper-method
+  nil)
+
+(defun org-babel-perl-evaluate (session body &optional result-type)
+  "Pass BODY to the Perl process in SESSION.  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, as elisp."
+  (if (not session)
+      ;; external process evaluation
+      (save-window-excursion
+        (case result-type
+          (output
+           (with-temp-buffer
+             (insert body)
+             ;; (message "buffer=%s" (buffer-string)) ;; debugging
+             (shell-command-on-region (point-min) (point-max) "perl" 'replace)
+             (buffer-string)))
+          (value
+           (let ((tmp-file (make-temp-file "perl-functional-results")))
+             (with-temp-buffer
+               (insert
+		(format
+		 (if (member "pp" result-params)
+                     (error "Pretty-printing not implemented for perl")
+                   org-babel-perl-wrapper-method)
+		 (let ((lines (split-string
+			       (org-remove-indentation (org-babel-trim body)) "[\r\n]")))
+		   (concat
+		    (mapconcat #'identity (butlast lines) "\n")
+		    (format "\nreturn %s" (car (last lines)))))
+		 tmp-file))
+               ;; (message "buffer=%s" (buffer-string)) ;; debugging
+               (shell-command-on-region (point-min) (point-max) "perl"))
+             (let ((raw (with-temp-buffer (insert-file-contents tmp-file) (buffer-string))))
+               (if (or (member "code" result-params) (member "pp" result-params))
+                   raw
+                 (org-babel-import-elisp-from-file tmp-file)))))))
+    ;; comint session evaluation
+    (error "Sessions are not supported for Perl.")))
+
+(provide 'org-babel-perl)
+;;; org-babel-perl.el ends here