Re: C-u prefix behavior of TAB broken

[Miles Bader]

martin rudalics <address@hidden> writes:
> For the case a prefix argument is given and the region is not active, we
> could try to set the region around the smallest containing form and call
> `indent-region' on that.  But that would be a different feature.

Can't indent-for-tab-command simply, if there's a prefix argument given,
rigidly indent the following sexp by the change in indentation?  That
doesn't seem hard at all, and matches the behavior I remember (perhaps
there are corner cases where it would differ, but I don't think I know
about them...).

For instance, the following isn't the most elegant code, but it seems to
do the right thing:

--- orig/lisp/indent.el
+++ mod/lisp/indent.el
@@ -99,13 +99,26 @@
             (or (> (current-column) (current-indentation))
                 (eq this-command last-command))))
     (insert-tab arg))
-   ;; Those functions are meant specifically for tabbing and not for
-   ;; indenting, so we can't pass them to indent-according-to-mode.
-   ((memq indent-line-function '(indent-relative indent-relative-maybe))
-    (funcall indent-line-function))
-   ;; Indent the line.
    (t
-    (indent-according-to-mode))))
+    (let ((end-marker (and arg (save-excursion (forward-sexp) (point-marker))))
+         (old-indent (current-indentation)))
+
+      ;; Those functions are meant specifically for tabbing and not for
+      ;; indenting, so we can't pass them to indent-according-to-mode.
+      (if (memq indent-line-function '(indent-relative indent-relative-maybe))
+         (funcall indent-line-function)
+       ;; Indent the line.
+       (indent-according-to-mode))
+
+      ;; If a prefix argument was given, rigidly indent the following
+      ;; sexp to match the change in the current line's indentation.
+      ;;
+      (when arg
+       (let ((indentation-change (- (current-indentation) old-indent)))
+         (save-excursion
+           (forward-line 1)
+           (when (< (point) end-marker)
+             (indent-rigidly (point) end-marker indentation-change)))))))))
 
 (defun insert-tab (&optional arg)
   (let ((count (prefix-numeric-value arg)))


-Miles

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