From: Michal Nazarewicz <mpn@google.com>
To: emacs-devel@gnu.org, Drew Adams <drew.adams@oracle.com>
Subject: [PATCHv3] Add cycle-spacing command.
Date: Thu, 17 Jan 2013 12:41:40 +0100 [thread overview]
Message-ID: <4a0822967f5a904ff6c1eaae77d2cc526c69858a.1358422492.git.mina86@mina86.com> (raw)
In-Reply-To: <ed2869c4c949a979e564e627ee41a96306d62969.1355151325.git.mina86@mina86.com>
From: Michal Nazarewicz <mina86@mina86.com>
This commit adds a cycle-spacing command which is, in a sense,
generalisation of the just-on-space command. When run continuously,
it cycles between having only one space, having no spaces and original
spacing.
---
So, any interest in this at all?
etc/NEWS | 5 +++
lisp/ChangeLog | 4 ++
lisp/simple.el | 86 ++++++++++++++++++++++++++++++++++++++++++++++----------
3 files changed, 80 insertions(+), 15 deletions(-)
diff --git a/etc/NEWS b/etc/NEWS
index 0471683..8400cd0 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -142,6 +142,11 @@ when its arg ADJACENT is non-nil (when called interactively with C-u C-u)
it works like the utility `uniq'. Otherwise by default it deletes
duplicate lines everywhere in the region without regard to adjacency.
+** New `cycle-spacing' command allows cycling between having just one
+space, no spaces, or reverting to the original spacing. Like
+`just-one-space' command it can handle or ignore newlines and use
+leave different number of spaces.
+
** Tramp
+++
*** New connection method "adb", which allows to access Android
diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 684beb5..096a2a3 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,7 @@
+2013-01-17 Michal Nazarewicz <mina86@mina86.com>
+
+ * simple.el: Add cycle-spacing command.
+
2013-01-17 Jürgen Hötzel <juergen@archlinux.org>
* eshell/esh-util.el (eshell-path-env): Make it buffer local, in
diff --git a/lisp/simple.el b/lisp/simple.el
index 847c07a..989b504 100644
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -742,25 +742,81 @@ If BACKWARD-ONLY is non-nil, only delete them before point."
(skip-chars-backward " \t")
(constrain-to-field nil orig-pos)))))
+(defvar cycle-spacing--context nil
+ "Store context used in consecutive calls to `cycle-spacing' command.
+The first time this function is run, it saves the original point
+position and original spacing around the point in this
+variable.")
+
+(defun cycle-spacing (&optional n preserve-nl-back single-shot)
+ "Manipulate spaces around the point in a smart way.
+
+When run as an interactive command, the first time it's called
+in a sequence, deletes all spaces and tabs around point leaving
+one (or N spaces). If this does not change content of the
+buffer, skips to the second step:
+
+When run for the second time in a sequence, deletes all the
+spaces it has previously inserted.
+
+When run for the third time, returns the whitespace and point in
+a state encountered when it had been run for the first time.
+
+For example, if buffer contains \"foo ^ bar\" with \"^\" donating the
+point, calling `cycle-spacing' command will replace two spaces with
+a single space, calling it again immediately after, will remove all
+spaces, and calling it for the third time will bring two spaces back
+together.
+
+If N is negative, delete newlines as well. However, if
+PRESERVE-NL-BACK is t new line characters prior to the point
+won't be removed.
+
+If SINGLE-SHOT is non-nil, will only perform the first step. In
+other words, it will work just like `just-on-space' command."
+ (interactive "*p")
+ (let ((orig-pos (point))
+ (skip-characters (if (and n (< n 0)) " \t\n\r" " \t"))
+ (n (abs (or n 1))))
+ (skip-chars-backward (if preserve-nl-back " \t" skip-characters))
+ (constrain-to-field nil orig-pos)
+ (cond
+ ;; Command run for the first time or single-shot is non-nil
+ ((or single-shot
+ (not (equal last-command this-command))
+ (not cycle-spacing--context))
+ (let* ((start (point))
+ (n (- n (skip-chars-forward " " (+ n (point)))))
+ (mid (point))
+ (end (progn
+ (skip-chars-forward skip-characters)
+ (constrain-to-field nil orig-pos t))))
+ (setq cycle-spacing--context ;; Save for later
+ ;; Special handling for case where there was no space at all
+ (unless (= start end)
+ (cons orig-pos (buffer-substring start (point)))))
+ ;; If this run causes no change in buffer content, delete all spaces,
+ ;; otherwise delete all excees spaces.
+ (delete-region (if (and (not single-shot) (zerop n) (= mid end))
+ start mid) end)
+ (dotimes (i n)
+ (insert ?\s))))
+
+ ;; Command run for the second time
+ ((not (equal orig-pos (point)))
+ (delete-region (point) orig-pos))
+
+ ;; Command run for the third time
+ (t
+ (insert (cdr cycle-spacing--context))
+ (goto-char (car cycle-spacing--context))
+ (setq cycle-spacing--context nil)))))
+
(defun just-one-space (&optional n)
"Delete all spaces and tabs around point, leaving one space (or N spaces).
If N is negative, delete newlines as well, leaving -N spaces."
(interactive "*p")
- (unless n (setq n 1))
- (let ((orig-pos (point))
- (skip-characters (if (< n 0) " \t\n\r" " \t"))
- (n (abs n)))
- (skip-chars-backward skip-characters)
- (constrain-to-field nil orig-pos)
- (dotimes (_ n)
- (if (= (following-char) ?\s)
- (forward-char 1)
- (insert ?\s)))
- (delete-region
- (point)
- (progn
- (skip-chars-forward skip-characters)
- (constrain-to-field nil orig-pos t)))))
+ (cycle-spacing n nil t))
\f
(defun beginning-of-buffer (&optional arg)
"Move point to the beginning of the buffer.
next prev parent reply other threads:[~2013-01-17 11:41 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-12-04 22:36 [PATCH] Add smart-space command Michal Nazarewicz
2012-12-04 22:55 ` Drew Adams
2012-12-04 23:11 ` Michal Nazarewicz
2012-12-10 14:57 ` [PATCHv2] Add cycle-spacing command Michal Nazarewicz
2013-01-17 11:41 ` Michal Nazarewicz [this message]
2013-01-17 13:06 ` [PATCHv3] " Lele Gaifax
2013-01-26 15:26 ` [PATCHv4] " Michal Nazarewicz
2013-01-26 17:14 ` Stephen J. Turnbull
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=4a0822967f5a904ff6c1eaae77d2cc526c69858a.1358422492.git.mina86@mina86.com \
--to=mpn@google.com \
--cc=drew.adams@oracle.com \
--cc=emacs-devel@gnu.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
Code repositories for project(s) associated with this external index
https://git.savannah.gnu.org/cgit/emacs.git
https://git.savannah.gnu.org/cgit/emacs/org-mode.git
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.