Here's the code from my version of org.el (9.5.5, inbuilt in Emacs 28.2). (defun org-babel-do-load-languages (sym value) "Load the languages defined in `org-babel-load-languages'." (set-default sym value) (dolist (pair org-babel-load-languages) (let ((active (cdr pair)) (lang (symbol-name (car pair)))) (if active (require (intern (concat "ob-" lang))) (fmakunbound (intern (concat "org-babel-execute:" lang))) (fmakunbound (intern (concat "org-babel-expand-body:" lang)))))))
1. Question from purely a programming student's perspective: this seems to be doing two things: (i) a set-default on line 3, and (ii) actually loading the language support libraries. If one were re-designing from scratch, without worrying about backward compatibility, would it be cleaner to separate the above into (defun org-babel-do-load-languages () ; no arguments "Load the languages defined in `org-babel-load-languages'." (interactive) ; why not? (dolist (pair org-babel-load-languages) ... )) and (defun org-babel-update-loaded-languages (value) ; value seems enough, don't need sym "Update the value of `org-babel-load-languages' and call org-babel-do-load-languages" (set-default ...)) 2. This question https://emacs.stackexchange.com/questions/20577/org-babel-load-all-languages-on-demand asks: is there any way for org-babel to load support for languages when I actually try to use a code block with that language? [as opposed to customising org-babel-load-languages or similar] and the accepted answer suggests the following: (defadvice org-babel-execute-src-block (around load-language nil activate) "Load language if needed" ... What would be the downside of making load-on-demand the default for all languages? Then people wouldn't have to customise org-babel-load-languages. Apologies if this is not the right list for such "idle curiosity" type questions, and thanks for any insights! -mandar