now using org-babel-tangle-langs to track file extensions and shebang lines

lisp/langs/org-babel-R.el

@@ -33,6 +33,8 @@
 
 (org-babel-add-interpreter "R")
 
+(add-to-list 'org-babel-tangle-langs '("R" "r"))
+
 (defun org-babel-execute:R (body params)
   "Execute a block of R code with org-babel.  This function is
 called by `org-babel-execute-src-block'."

lisp/langs/org-babel-lisp.el

@@ -33,6 +33,8 @@
 
 (org-babel-add-interpreter "emacs-lisp")
 
+(add-to-list 'org-babel-tangle-langs '("emacs-lisp" "el"))
+
 (defun org-babel-execute:emacs-lisp (body params)
   "Execute a block of emacs-lisp code with org-babel.  This
 function is called by `org-babel-execute-src-block'."

lisp/langs/org-babel-python.el

@@ -34,6 +34,8 @@
 
 (org-babel-add-interpreter "python")
 
+(add-to-list 'org-babel-tangle-langs '("python" "py" "#!/usr/bin/env 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'."

lisp/langs/org-babel-ruby.el

@@ -34,6 +34,8 @@
 
 (org-babel-add-interpreter "ruby")
 
+(add-to-list 'org-babel-tangle-langs '("ruby" "rb" "#!/usr/bin/env ruby"))
+
 (defun org-babel-execute:ruby (body params)
   "Execute a block of Ruby code with org-babel.  This function is
 called by `org-babel-execute-src-block'."

lisp/langs/org-babel-sh.el

@@ -34,6 +34,8 @@
 
 (org-babel-add-interpreter "sh")
 
+(add-to-list 'org-babel-tangle-langs '("sh" "sh" "#!/usr/bin/env sh"))
+
 (defun org-babel-execute:sh (body params)
   "Execute a block of Shell commands with org-babel.  This
 function is called by `org-babel-execute-src-block'."

lisp/org-babel-tangle.el

@@ -31,5 +31,12 @@
 ;;; Code:
 (require 'org-babel)
 
+(defvar org-babel-tangle-langs nil
+  "Association list matching source-block languages.  The car of
+each element should be a string indicating the source block
+language, and the cdr should be a list containing the extension
+and shebang(#!) line to use when writing out the language to
+file.")
+
 (provide 'org-babel-tangle)
 ;;; org-babel-tangle.el ends here