New minor mode Electric Quote

This lets you easily insert quotes ‘like this’ by typing
quotes `like this', and similarly you can easily insert
quotes “like this” by typing quotes ``like this'' (Bug#20545).
* doc/emacs/basic.texi (Inserting Text):
* doc/emacs/modes.texi (Minor Modes):
* etc/NEWS: Document it.
* doc/emacs/text.texi (Quotation Marks): New section.
* lisp/electric.el (electric-quote-comment)
(electric-quote-string, electric-quote-paragraph):
New custom vars.
(electric--insertable-p)
(electric-quote-post-self-insert-function): New functions.
(electric-quote-mode, electric-quote-local-mode): New minor modes.
* lisp/progmodes/elisp-mode.el (emacs-lisp-mode):
Add curved single quotes to electric-pair-text-pairs.
Set electric-quote-string in this buffer.

3 files changed, 54 insertions, 0 deletions

diff --git a/doc/emacs/basic.texi b/doc/emacs/basic.texi
index be45856a6dd..cc9602e8c52 100644
--- a/doc/emacs/basic.texi
+++ b/doc/emacs/basic.texi
@@ -127,6 +127,12 @@ sign (Unicode code-point @code{U+221E}):
   A numeric argument to @kbd{C-q} or @kbd{C-x 8 @key{RET}} specifies
 how many copies of the character to insert (@pxref{Arguments}).
 
+  In some contexts, if you type a quotation using grave accent and
+apostrophe @t{`like this'}, it is converted to a form @t{‘like this’}
+using single quotation marks.  Similarly, typing a quotation @t{``like
+this''} using double grave accent and apostrophe converts it to a form
+@t{“like this”} using double quotation marks.  @xref{Quotation Marks}.
+
 @node Moving Point
 @section Changing the Location of Point
 
diff --git a/doc/emacs/modes.texi b/doc/emacs/modes.texi
index 0e8f46a666d..e79561ac008 100644
--- a/doc/emacs/modes.texi
+++ b/doc/emacs/modes.texi
@@ -200,6 +200,12 @@ Auto Save mode saves the buffer contents periodically to reduce the
 amount of work you can lose in case of a crash.  @xref{Auto Save}.
 
 @item
+Electric Quote mode automatically converts quotation marks.  For
+example, it requotes text typed @t{`like this'} to text @t{‘like
+this’}.  You can control what kind of text it operates in, and you can
+disable it entirely in individual buffers.  @xref{Quotation Marks}.
+
+@item
 Enriched mode enables editing and saving of formatted text.
 @xref{Enriched Text}.
 
diff --git a/doc/emacs/text.texi b/doc/emacs/text.texi
index 9bc5ade81a2..d891cc16870 100644
--- a/doc/emacs/text.texi
+++ b/doc/emacs/text.texi
@@ -69,6 +69,7 @@ for editing such pictures.
 * Sentences::           Moving over and killing sentences.
 * Paragraphs::          Moving over paragraphs.
 * Pages::               Moving over pages.
+* Quotation Marks::     Inserting quotation marks.
 * Filling::             Filling or justifying text.
 * Case::                Changing the case of text.
 * Text Mode::           The major modes for editing text files.
@@ -404,6 +405,47 @@ that separates pages (@pxref{Regexps}).  The normal value of this
 variable is @code{"^\f"}, which matches a formfeed character at the
 beginning of a line.
 
+@node Quotation Marks
+@section Quotation Marks
+@cindex Quotation marks
+@cindex Electric Quote mode
+@cindex mode, Electric Quote
+@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
+this"}.  Another common way is the curved quote convention, which uses
+left and right single or double quotation marks @t{‘like this’} or
+@t{“like this”}.  Typewriter quotes are simple and portable; curved
+quotes are less ambiguous and typically look nicer.
+
+  Electric Quote mode makes it easier to type curved quotes.  It
+optionally converts a quotation's grave accent and apostrophe @t{`like
+this'} to single quotation marks @t{‘like this’}.  Similarly, it
+converts a quotation's double grave accent and double apostrophe
+@t{``like this''} to double quotation marks @t{“like this”}.  These
+conversions are suppressed in buffers whose coding systems cannot
+represent curved quote characters.
+
+@vindex electric-quote-paragraph
+@vindex electric-quote-comment
+@vindex electric-quote-string
+  You can customize the behavior of Electric Quote mode by customizing
+variables that control where it is active.  It is active in text
+paragraphs if @code{electric-quote-paragraph} is non-@code{nil}, in
+programming-language comments if @code{electric-quote-comment} is
+non-@code{nil}, and in programming-language strings if
+@code{electric-quote-string} is non-@code{nil}.  The default is
+@code{nil} for @code{electric-quote-string} and @code{t} for the other
+variables.
+
+  Electric Quote mode is disabled by default.  To toggle it, type
+@kbd{M-x electric-quote-mode}.  To toggle it in a single buffer, use
+@kbd{M-x electric-quote-local-mode}.  To suppress it for a single use,
+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, use @kbd{C-x 8 @key{RET}} (@code{insert-char}).
+@xref{Inserting Text}.
+
 @node Filling
 @section Filling Text
 @cindex filling text