[O] [PATCH] Common Lisp source blocks are now wrapped in a LET form which binds the symbol *default-pathname-defaults* to the directory in which the org file resides.

[Mark Cox]

Hi,

This may be contentious and break backward compatibility for some people.

Currently, relative pathnames in Common Lisp source blocks are
meaningless as the *default-pathname-defaults* symbol is set to
whatever the value is when SLIME was invoked. This behaviour is
contrary to the shell source block processor (I haven't checked the
others).

This is in /tmp/example1/test.org
#+begin_src sh
pwd
#+end_src

#+results:
: #P"/tmp/example1/"

This is in /tmp/example2/test.org
#+begin_src sh
pwd
#+end_src

#+results:
: #P"/tmp/example2/"

The attached patch brings this expected behaviour (well from my point
of view) to lisp source blocks. Given the behaviour of Emacs commands
like DIRED and COMPILE, I think the patch makes things more
consistent.

I couldn't figure out how the sh block processor determines the path
to the org file so I hacked together something that works using some
of the Org hooks.

Thanks
Mark

lisp/ob-lisp.el: Added new variable ORG-BABEL-LISP-CURRENT-BUFFER
which is used to store a reference to the currently being processed org file.
This variable is setq'd in the hooks for
ORG-BABEL-PRE-TANGLE-HOOK, ORG-CTRL-C-CTRL-C-HOOK and
ORG-EXPORT-FIRST-HOOK.

lisp/ob-lisp.el (org-babel-expand-body:lisp): The code sent to SLIME
is now wrapped in a LET block which binds
COMMON-LISP:*DEFAULT-PATHNAME-DEFAULTS* to the directory where the
currently being processed org file resides.

diff --git a/lisp/ob-lisp.el b/lisp/ob-lisp.el
index a875d55..db06182 100644
--- a/lisp/ob-lisp.el
+++ b/lisp/ob-lisp.el
@@ -40,6 +40,14 @@

 (defvar org-babel-default-header-args:lisp '())
 (defvar org-babel-header-arg-names:lisp '(package))
+(defvar org-babel-lisp-current-buffer nil)
+
+(let ((fn (lambda ()
+           (setq org-babel-lisp-current-buffer (current-buffer))
+           nil)))
+  (dolist (hook '(org-babel-pre-tangle-hook org-ctrl-c-ctrl-c-hook
org-export-first-hook))
+    (add-hook hook fn)))
+

 (defun org-babel-expand-body:lisp (body params)
   "Expand BODY according to PARAMS, return the expanded body."
@@ -73,8 +81,10 @@
                (read (org-bable-lisp-vector-to-list (cadr result)))
              (error (cadr result)))))
       (slime-eval `(swank:eval-and-grab-output
-                   ,(format "(progn %s)" (buffer-substring-no-properties
-                                          (point-min) (point-max))))
+                   ,(format "(let
((common-lisp:*default-pathname-defaults* #P%S)) %s)"
+                            (file-name-directory (buffer-file-name
org-babel-lisp-current-buffer))
+                            (buffer-substring-no-properties
+                             (point-min) (point-max))))
                  (cdr (assoc :package params)))))
    (org-babel-pick-name (cdr (assoc :colname-names params))
                        (cdr (assoc :colnames params)))