Re: [O] Babel eval w/ C-c C-c but not (org-babel-execute-buffer)

[Ken Mankoff]

Hello,

I think that even when ":eval no" is set, eval should happen if the user 
explicitly requests it.

The use case is that I have code that takes an unreasonable amount of compute 
time to run it in Emacs (e.g. a full day of compute time). I think even with 
:async this type of code should be run outside of emacs, so I tangle it and run 
the python or bash scripts in a terminal.

Elsewhere in the project (Org file) I have babel blocks that I want to update 
throughout the file. I do this by cleaning all result blocks with =C-u C-c C-v 
k= or (org-babel-remove-result-one-or-many), then executing all blocks (without 
=:eval no=) using =C-c C-v C-b= or (org-babel-execute-buffer).

In order to not spend days of compute time when I eval 
(org-babel-execute-buffer), I set :eval no to the computationally heavy babel 
blocks. But during development it would be nice to run these... hence the 
conflict with the current Org behavior and my desire for a new feature.

The two-line change at the bottom implements the following behavior:

When the prefix arg is passed to org-babel-execute-src-block, the block is 
evaluated regardless of the :eval flag.

Note that this doubles up on the prefix arg behavior, which is already set 
according to the documentation:

> With prefix argument ARG, force re-execution even if an existing
> result cached in the buffer would otherwise have been returned.

Questions for the list:

Is this feature something that makes sense?

If yes, then do you also think that tangling should occur when explicitly 
requested (i.e. C-u C-c C-v C-t), even if :tangle no is set?

Suggestions for a better implementation?

Thanks,

  -k.


diff --git a/lisp/ob-core.el b/lisp/ob-core.el
index 572f97919..9f9add334 100644
--- a/lisp/ob-core.el
+++ b/lisp/ob-core.el
@@ -646,7 +646,7 @@ block."
     ;; Merge PARAMS with INFO before considering source block
     ;; evaluation since both could disagree.
     (cl-callf org-babel-merge-params (nth 2 info) params)
-    (when (org-babel-check-evaluate info)
+    (when (or arg (org-babel-check-evaluate info))
       (cl-callf org-babel-process-params (nth 2 info))
       (let* ((params (nth 2 info))
             (cache (let ((c (cdr (assq :cache params))))
@@ -663,7 +663,7 @@ block."
            (let ((result (org-babel-read-result)))
              (message (replace-regexp-in-string "%" "%%" (format "%S" result)))
              result)))
-        ((org-babel-confirm-evaluate info)
+         ((or arg (org-babel-confirm-evaluate info))
          (let* ((lang (nth 0 info))
                 (result-params (cdr (assq :result-params params)))
                 ;; Expand noweb references in BODY and remove any