[PATCH] org-indent: Allow indentation per level to be 0

[David Lukes]

* lisp/org-indent.el (org-indent--compute-prefixes): Prefixes should
only be computed when `org-indent-indentation-per-level' is greater than
0.  For one thing, the current algorithm leads to an error otherwise,
and for another, this makes it possible to use org-indent just to
preserve indentation on continuation lines, without adding any
additional indentation per level (by setting the option to 0).

TINYCHANGE
---
 lisp/org-indent.el | 49 +++++++++++++++++++++++-----------------------
 1 file changed, 25 insertions(+), 24 deletions(-)

diff --git a/lisp/org-indent.el b/lisp/org-indent.el
index ea7ea071b..b87cc4e5f 100644
--- a/lisp/org-indent.el
+++ b/lisp/org-indent.el
@@ -126,31 +126,32 @@ useful to make it ever so slightly different."
        (make-vector org-indent--deepest-level nil))
   (setq org-indent--text-line-prefixes
        (make-vector org-indent--deepest-level nil))
-  (dotimes (n org-indent--deepest-level)
-    (let ((indentation (if (<= n 1) 0
-                        (* (1- org-indent-indentation-per-level)
-                           (1- n)))))
-      ;; Headlines line prefixes.
-      (let ((heading-prefix (make-string indentation ?*)))
-       (aset org-indent--heading-line-prefixes
+  (when (> org-indent-indentation-per-level 0)
+    (dotimes (n org-indent--deepest-level)
+      (let ((indentation (if (<= n 1) 0
+                          (* (1- org-indent-indentation-per-level)
+                             (1- n)))))
+        ;; Headlines line prefixes.
+        (let ((heading-prefix (make-string indentation ?*)))
+         (aset org-indent--heading-line-prefixes
+               n
+               (org-add-props heading-prefix nil 'face 'org-indent))
+         ;; Inline tasks line prefixes
+         (aset org-indent--inlinetask-line-prefixes
+               n
+               (cond ((<= n 1) "")
+                     ((bound-and-true-p org-inlinetask-show-first-star)
+                      (concat org-indent-inlinetask-first-star
+                              (substring heading-prefix 1)))
+                     (t (org-add-props heading-prefix nil 'face 
'org-indent)))))
+        ;; Text line prefixes.
+        (aset org-indent--text-line-prefixes
              n
-             (org-add-props heading-prefix nil 'face 'org-indent))
-       ;; Inline tasks line prefixes
-       (aset org-indent--inlinetask-line-prefixes
-             n
-             (cond ((<= n 1) "")
-                   ((bound-and-true-p org-inlinetask-show-first-star)
-                    (concat org-indent-inlinetask-first-star
-                            (substring heading-prefix 1)))
-                   (t (org-add-props heading-prefix nil 'face 'org-indent)))))
-      ;; Text line prefixes.
-      (aset org-indent--text-line-prefixes
-           n
-           (org-add-props
-               (concat (make-string (+ n indentation) ?\s)
-                       (and (> n 0)
-                            (char-to-string org-indent-boundary-char)))
-               nil 'face 'org-indent)))))
+             (org-add-props
+              (concat (make-string (+ n indentation) ?\s)
+                      (and (> n 0)
+                           (char-to-string org-indent-boundary-char)))
+              nil 'face 'org-indent))))))
 
 (defsubst org-indent-remove-properties (beg end)
   "Remove indentations between BEG and END."
-- 
2.32.0