Re: [PATCH] Enable customisation for electric-quote-mode chars

[Göktuğ Kayaalp]

On 2016-10-06 02:31:44 PM -0700, Paul Eggert <address@hidden> wrote:
> On 10/05/2016 11:40 PM, Eli Zaretskii wrote:
>> His assignment is complete, so we can proceed with using the patch.
>
> Thanks. Göktuğ, can you please point me at the latest version of this 
> patch? I've lost context.
>

Hello, I'll attach the next version of the patch.  The only change (to
the patch) is in the ‘etc/NEWS’ file, the rest is the same.  I'm rather
uninitiated about the conventions regarding that file, so please warn me
if anything's wrong, I'll fix ASAP.

The majority of this thread is on the end of september BTW, and there
are some messages on 1st october (just noting in case you want to
review).

-- 
İ. Göktuğ Kayaalp.
http://gkayaalp.com/

diff --git a/doc/emacs/text.texi b/doc/emacs/text.texi
index 579f788..74b68dd 100644
--- a/doc/emacs/text.texi
+++ b/doc/emacs/text.texi
@@ -412,6 +412,7 @@ beginning of a line.
 @cindex mode, Electric Quote
 @cindex curly quotes
 @cindex curved quotes
address@hidden guillemets
 @findex electric-quote-mode
   One common way to quote is the typewriter convention, which quotes
 using straight apostrophes @t{'like this'} or double-quotes @t{"like
@@ -420,11 +421,17 @@ left and right single or double quotation marks @t{‘like 
this’} or
 @t{“like this”}.  In text files, typewriter quotes are simple and
 portable; curved quotes are less ambiguous and typically look nicer.
 
address@hidden electric-quote-chars
   Electric Quote mode makes it easier to type curved quotes.  As you
 type characters it optionally converts @t{`} to @t{‘}, @t{'} to @t{’},
 @t{``} to @t{“}, and @t{''} to @t{”}.  These conversions are
 suppressed in buffers whose coding systems cannot represent curved
-quote characters.
+quote characters.  It's possible to change the default quotes listed
+above, by customizing the variable @code{electric-quote-chars}, a list
+of four characters, where the items correspond to the left single
+quote, the right single quote, the left double quote and the right
+double quote, respectively, whose default value is
address@hidden'(?‘ ?’ ?“ ?”)}.
 
 @vindex electric-quote-paragraph
 @vindex electric-quote-comment
@@ -445,7 +452,10 @@ type @kbd{C-q `} or @kbd{C-q '} instead of @kbd{`} or 
@kbd{'}.  To
 insert a curved quote even when Electric Quote is disabled or
 inactive, you can type @kbd{C-x 8 [} for @t{‘}, @kbd{C-x 8 ]} for
 @t{’}, @kbd{C-x 8 @{} for @t{“}, and @kbd{C-x 8 @}} for @t{”}.
address@hidden Text}.
address@hidden Text}.  Note that the value of
address@hidden does not affect these keybindings, they
+are not keybindings of @code{electric-quote-mode} but bound in
address@hidden
 
 @node Filling
 @section Filling Text
diff --git a/etc/NEWS b/etc/NEWS
index bd94c94..323f0b1 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -60,6 +60,10 @@ affected by this, as SGI stopped supporting IRIX in December 
2013.
 

 * Changes in Emacs 26.1
++++
+** The new user variable 'electric-quote-chars' provides a list
+of curved quotes for 'electric-quote-mode', allowing user to choose
+the types of quotes to be used.
 
 +++
 ** The new function 'call-shell-region' executes a command in an
diff --git a/lisp/electric.el b/lisp/electric.el
index 0ec0a1e..a846a78 100644
--- a/lisp/electric.el
+++ b/lisp/electric.el
@@ -425,16 +425,26 @@ The variable `electric-layout-rules' says when and how to 
insert newlines."
   :version "25.1"
   :type 'boolean :safe 'booleanp :group 'electricity)
 
+(defcustom electric-quote-chars '(?‘ ?’ ?“ ?”)
+  "Curved quote characters for `electric-quote-mode'.
+The items correspond to the left single quote, the right single
+quote, the left double quote, and the right double quote, respectively."
+  :version "25.1"
+  :type 'list :safe 'listp :group 'electricity)
+
 (defcustom electric-quote-paragraph t
   "Non-nil means to use electric quoting in text paragraphs."
   :version "25.1"
   :type 'boolean :safe 'booleanp :group 'electricity)
 
-(defun electric--insertable-p (string)
-  (or (not buffer-file-coding-system)
-      (eq (coding-system-base buffer-file-coding-system) 'undecided)
-      (not (unencodable-char-position nil nil buffer-file-coding-system
-                                      nil string))))
+(defun electric--insertable-p (string-or-char)
+  (let ((str (if (characterp string-or-char)
+                 (string string-or-char)
+               string-or-char)))
+    (or (not buffer-file-coding-system)
+        (eq (coding-system-base buffer-file-coding-system) 'undecided)
+        (not (unencodable-char-position nil nil buffer-file-coding-system
+                                        nil str)))))
 
 (defun electric-quote-post-self-insert-function ()
   "Function that `electric-quote-mode' adds to `post-self-insert-hook'.
@@ -457,30 +467,33 @@ This requotes when a quoting key is typed."
                   (derived-mode-p 'text-mode)
                   (or (eq last-command-event ?\`)
                       (save-excursion (backward-paragraph) (point)))))))
-      (when start
-        (save-excursion
-          (if (eq last-command-event ?\`)
-              (cond ((and (electric--insertable-p "“")
-                          (search-backward "‘`" (- (point) 2) t))
-                     (replace-match "“")
-                     (when (and electric-pair-mode
-                                (eq (cdr-safe
-                                     (assq ?‘ electric-pair-text-pairs))
-                                    (char-after)))
-                       (delete-char 1))
-                     (setq last-command-event ?“))
-                    ((and (electric--insertable-p "‘")
-                          (search-backward "`" (1- (point)) t))
-                     (replace-match "‘")
-                     (setq last-command-event ?‘)))
-            (cond ((and (electric--insertable-p "”")
-                        (search-backward "’'" (- (point) 2) t))
-                   (replace-match "”")
-                   (setq last-command-event ?”))
-                  ((and (electric--insertable-p "’")
-                        (search-backward "'" (1- (point)) t))
-                   (replace-match "’")
-                   (setq last-command-event ?’)))))))))
+      (pcase electric-quote-chars
+        (`(,q1 ,q2 ,q3 ,q4) 
+         (when start
+           (save-excursion
+             (if (eq last-command-event ?\`)
+                 (cond ((and (electric--insertable-p q3)
+                             (search-backward (string q1 ?`) (- (point) 2) t))
+                        (replace-match (string q3))
+                        (when (and electric-pair-mode
+                                   (eq (cdr-safe
+                                        (assq q1 electric-pair-text-pairs))
+                                       (char-after)))
+                          (delete-char 1))
+                        (setq last-command-event q3))
+                       ((and (electric--insertable-p q1)
+                             (search-backward "`" (1- (point)) t))
+                        (replace-match (string q1))
+                        (setq last-command-event q1)))
+               (cond ((and (electric--insertable-p q4)
+                           (search-backward (string q2 ?') (- (point) 2) t))
+                      (replace-match (string q4))
+                      (setq last-command-event q4))
+                     ((and (electric--insertable-p q2)
+                           (search-backward "'" (1- (point)) t))
+                      (replace-match (string q2))
+                      (setq last-command-event q2)))))))
+        (_ (error "‘electric-quote-chars’ must contain exactly 4 
characters."))))))
 
 (put 'electric-quote-post-self-insert-function 'priority 10)
 
@@ -497,6 +510,9 @@ and text paragraphs, and these are selectively controlled 
with
 `electric-quote-comment', `electric-quote-string', and
 `electric-quote-paragraph'.
 
+Customize `electric-quote-chars' in order to use quote chars
+other than the ones listed here.
+
 This is a global minor mode.  To toggle the mode in a single buffer,
 use `electric-quote-local-mode'."
   :global t :group 'electricity