30.5.3 Explicit Fill Commands
- Fill current paragraph (
- C-x f
- Set the fill column (
- M-x fill-region
- Fill each paragraph in the region (
- M-x fill-region-as-paragraph
- Fill the region, considering it as one paragraph.
- Center a line.
To refill a paragraph, use the command M-q
fill-paragraph). This operates on the paragraph that point is
inside, or the one after point if point is between paragraphs.
Refilling works by removing all the line-breaks, then inserting new ones
To refill many paragraphs, use M-x fill-region, which
divides the region into paragraphs and fills each of them.
fill-region use the same criteria as M-h
for finding paragraph boundaries (see Paragraphs). For more
control, you can use M-x fill-region-as-paragraph, which refills
everything between point and mark. This command deletes any blank lines
within the region, so separate blocks of text end up combined into one
A numeric argument to M-q causes it to justify the text as
well as filling it. This means that extra spaces are inserted to make
the right margin line up exactly at the fill column. To remove the
extra spaces, use M-q with no argument. (Likewise for
fill-region.) Another way to control justification, and choose
other styles of filling, is with the
justification text property;
see Format Justification.
The command M-s (
center-line) centers the current line
within the current fill column. With an argument n, it centers
n lines individually and moves past them. This binding is
made by Text mode and is available only in that and related modes
(see Text Mode).
The maximum line width for filling is in the variable
fill-column. Altering the value of
fill-column makes it
local to the current buffer; until that time, the default value is in
effect. The default is initially 70. See Locals. The easiest way
fill-column is to use the command C-x f
set-fill-column). With a numeric argument, it uses that as the
new fill column. With just C-u as argument, it sets
fill-column to the current horizontal position of point.
Emacs commands normally consider a period followed by two spaces or by
a newline as the end of a sentence; a period followed by just one space
indicates an abbreviation and not the end of a sentence. To preserve
the distinction between these two ways of using a period, the fill
commands do not break a line after a period followed by just one space.
If the variable
fill commands expect and leave just one space at the end of a sentence.
Ordinarily this variable is
t, so the fill commands insist on
two spaces for the end of a sentence, as explained above. See Sentences.
If the variable
colon-double-space is non-
fill commands put two spaces after a colon.
Some languages do not use period to indicate end of sentence. For
example, a sentence in Thai text ends with double space but without a
period. Set the variable
t to tell the sentence commands that a period is not necessary.
fill-nobreak-predicate specifies additional
conditions for where line-breaking is allowed. Its value is either
nil or a Lisp function; the function is called with no
arguments, and if it returns a non-
nil value, then point is not
a good place to break the line. Two standard functions you can use are
fill-single-word-nobreak-p (don't break after the first word of
a sentence or before the last) and
break after ‘(’ or before ‘)’, ‘:’ or ‘?’).