This section describes higher-level commands for deleting text, commands intended primarily for the user but useful also in Lisp programs.
This function deletes all spaces and tabs around point. It returns
nil.
If backward-only is non-nil, the function deletes
spaces and tabs before point, but not after point.
In the following examples, we call delete-horizontal-space four
times, once on each line, with point between the second and third
characters on the line each time.
---------- Buffer: foo ---------- I ∗thought I ∗ thought We∗ thought Yo∗u thought ---------- Buffer: foo ----------
(delete-horizontal-space) ; Four times.
⇒ nil
---------- Buffer: foo ----------
Ithought
Ithought
Wethought
You thought
---------- Buffer: foo ----------
This function joins the line point is on to the previous line, deleting
any whitespace at the join and in some cases replacing it with one
space. If join-following-p is non-nil,
delete-indentation joins this line to the following line
instead. Otherwise, if beg and end are non-nil,
this function joins all lines in the region they define.
In an interactive call, join-following-p is the prefix argument,
and beg and end are, respectively, the start and end of
the region if it is active, else nil. The function returns
nil.
If there is a fill prefix, and the second of the lines being joined
starts with the prefix, then delete-indentation deletes the
fill prefix before joining the lines. See Margins for Filling.
In the example below, point is located on the line starting ‘events’, and it makes no difference if there are trailing spaces in the preceding line.
---------- Buffer: foo ---------- When in the course of human ∗ events, it becomes necessary ---------- Buffer: foo ----------
(delete-indentation)
⇒ nil
---------- Buffer: foo ---------- When in the course of human∗ events, it becomes necessary ---------- Buffer: foo ----------
After the lines are joined, the function fixup-whitespace is
responsible for deciding whether to leave a space at the junction.
This function replaces all the horizontal whitespace surrounding point
with either one space or no space, according to the context. It
returns nil.
At the beginning or end of a line, the appropriate amount of space is none. Before a character with close parenthesis syntax, or after a character with open parenthesis or expression-prefix syntax, no space is also appropriate. Otherwise, one space is appropriate. See Table of Syntax Classes.
In the example below, fixup-whitespace is called the first time
with point before the word ‘spaces’ in the first line. For the
second invocation, point is directly after the ‘(’.
---------- Buffer: foo ---------- This has too many ∗spaces This has too many spaces at the start of (∗ this list) ---------- Buffer: foo ----------
(fixup-whitespace)
⇒ nil
(fixup-whitespace)
⇒ nil
---------- Buffer: foo ---------- This has too many spaces This has too many spaces at the start of (this list) ---------- Buffer: foo ----------
This command replaces any spaces and tabs around point with a single
space, or n spaces if n is specified. It returns
nil.
This function deletes blank lines surrounding point. If point is on a blank line with one or more blank lines before or after it, then all but one of them are deleted. If point is on an isolated blank line, then it is deleted. If point is on a nonblank line, the command deletes all blank lines immediately following it.
A blank line is defined as a line containing only tabs and spaces.
delete-blank-lines returns nil.
Delete trailing whitespace in the region defined by start and end.
This command deletes whitespace characters after the last non-whitespace character in each line in the region.
If this command acts on the entire buffer (i.e., if called
interactively with the mark inactive, or called from Lisp with
end nil), it also deletes all trailing lines at the end of the
buffer if the variable delete-trailing-lines is non-nil.