Repeating a command n times

Question

For posting code to stackexchange I repeatedly have to do indentation in emacs. I mark a piece of text and then do M-X indent-rigidly four times. Is there an elegant way to do this indentation of text by four blanks in one go?

Answer 1

The documentation for indent-rigidly says:

If called from a program, or interactively with prefix ARG, indent all lines starting in the region forward by ARG columns. If called from a program, START and END specify the beginning and end of the text to act on, in place of the region.

To indent by four columns, just pass the prefix argument with C-u:

C-u C-x TAB

Answer 2

Besides the obvious answer of using a prefix arg to specify the number of columns to indent (i.e., C-4 C-x TAB), if you use Emacs 24.4 or later then you can simply use arrow keys to repeat indenting, i.e., to incrementally indent. E.g.:

C-x TAB <right> <right> <right>...

If you use Shift with <right> or <left> then each repetition indents by a tab stop. Without Shift, each repetition indents by one column.

Answer 3

I've written this snippet when Stack Overflow for some reason stopped recognizing lisp syntax in the code blocks. Might be useful:

(defun stackoverflow-block (beg end)
  (interactive "r")
  (let ((str (buffer-substring-no-properties beg end)))
    (delete-region beg end)
    (insert
     "<!-- language: lang-lisp -->\n\n"
     (mapconcat
      (lambda (x) (format "    %s" x))
      (split-string str "\n")
      "\n"))))

Answer 4

I've always used M-[number] to do things. This also works if you just want to type out 80/132 characters to measure the width of your screen or something. There doesn't seem to be a limit on the number of numbers you can put in the prefix.

M-80 #
;;Prints out 80 #

M-4 M-x indent-rigidly
;; Indents 4 times

;; Need to separate M-# with C-u if your command is a number
M-80 C-u 0
;; Prints out eighty 0 characters