Re: [PATCH] Implement texinfo @ref dwim

[Robert Pluim]

Eli Zaretskii <address@hidden> writes:

>> From: Robert Pluim <address@hidden>
>> Date: Tue, 05 Feb 2019 13:10:07 +0100
>> 
>> This has been sitting around in my patch queue for a while, and Iʼd
>> like to get it in so I can also get the manual update into the texinfo
>> project. I think Iʼve addressed all the comments from the last time
>> around.
>
> Thanks, I think this command will be useful.
>
>> * etc/NEWS: Describe new texinfo dwim reference functionality.
>
> I understand that the corresponding update to the Texinfo manual will
> be submitted to the Texinfo maintainers?  If so, the NEWS entry should
> be marked with "+++", I think.
>

Yes and yes.

>> +(define-skeleton address@hidden
>> +  "Insert appropriate address@hidden', address@hidden', or address@hidden' 
>> command.
>                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> Is Emacs smart enough not to highlight these as links?
>

You mean in (describe-function 'address@hidden)? They show
up unadorned.

>> +   ;; parenthesis
>> +   ((eq (char-before) ?\()
>> +    "@pxref{")
>
> @pxref is also good inside parentheses, not just after the opening
> paren.  Can this command be smarter and support also cases like
>
>   (bla-bla yak-yak @pxref{foo})
>
> ?

Yes, thatʼs possible. Iʼve limited the opening parenthesis to being on
the same or previous line though (I donʼt want excessive backwards
matching).

>> +   ;; beginning of sentence
>> +   ((looking-back (sentence-end) (point-at-bol 0))
>> +    "@xref{")
>
> What about BOB?  Can we produce @xref there as well?

Yes.

Revised version attached.

>From d38394e5d54fe1c7997634bb2ebd966a36a52f82 Mon Sep 17 00:00:00 2001
From: Robert Pluim <address@hidden>
Date: Tue, 5 Feb 2019 20:38:39 +0100
Subject: [PATCH] Add dwim function for inserting @ref variants
To: address@hidden

* lisp/textmodes/texinfo.el (address@hidden): New function.
Insert @ref variant based on surrounding context.
(texinfo-mode-map): Add binding for address@hidden

* etc/NEWS: Describe new texinfo dwim reference functionality.
---
 etc/NEWS                  |  9 +++++++++
 lisp/textmodes/texinfo.el | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 42 insertions(+)

diff --git a/etc/NEWS b/etc/NEWS
index 9bbe6befcf..5c06edd00a 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -472,6 +472,15 @@ To enable it, set the new defcustom 
'diff-font-lock-prettify' to t.
 of the file under version control if point is on an old changed line,
 or to the new revision of the file otherwise.
 
+** Texinfo
+
++++
+*** New function for inserting @pxref, @xref, or @ref commands.
+The function 'address@hidden', bound to 'C-c C-c r' by
+default, inserts one of three types of references based on the text
+surrounding point, namely @pxref near a parenthesis, @xref at the
+start of a sentence or at (point-min), else @ref.
+
 ** Browse-url
 
 *** The function 'browse-url-emacs' can now visit a URL in selected window.
diff --git a/lisp/textmodes/texinfo.el b/lisp/textmodes/texinfo.el
index 1a900122f9..71cdcab57e 100644
--- a/lisp/textmodes/texinfo.el
+++ b/lisp/textmodes/texinfo.el
@@ -470,6 +470,7 @@ texinfo-mode-map
     (define-key map "\C-c\C-cu"    'address@hidden)
     (define-key map "\C-c\C-ct"    'address@hidden)
     (define-key map "\C-c\C-cs"    'address@hidden)
+    (define-key map "\C-c\C-cr"    'address@hidden)
     (define-key map "\C-c\C-cq"    'address@hidden)
     (define-key map "\C-c\C-co"    'address@hidden)
     (define-key map "\C-c\C-cn"    'address@hidden)
@@ -825,6 +826,38 @@ address@hidden
   "Insert the string address@hidden' in a Texinfo buffer."
   \n "@quotation" \n _ \n)
 
+(define-skeleton address@hidden
+  "Insert appropriate address@hidden', address@hidden', or address@hidden' 
command.
+
+Looks at text around point to decide what to insert; an unclosed
+preceding open parenthesis results in '@pxref{}', point at the
+beginning of a sentence or at (point-min) yields '@xref{}', any
+other location (including inside a word), will result in '@ref{}'
+at the nearest previous whitespace or beginning-of-line.  A
+numeric argument says how many words the braces should surround.
+The default is not to surround any existing words with the
+braces."
+  nil
+  (cond
+   ;; parenthesis
+   ((looking-back "([^)]*" (point-at-bol 0))
+    "@pxref{")
+   ;; beginning of sentence or buffer
+   ((or (looking-back (sentence-end) (point-at-bol 0))
+        (= (point) (point-min)))
+    "@xref{")
+   ;; bol or eol
+   ((looking-at "^\\|$")
+    "@ref{")
+   ;; inside word
+   ((not (eq (char-syntax (char-after)) ? ))
+    (skip-syntax-backward "^ " (point-at-bol))
+    "@ref{")
+   ;; everything else
+   (t
+    "@ref{"))
+  _ "}")
+
 (define-skeleton address@hidden
   "Insert a address@hidden' command in a Texinfo buffer.
 A numeric argument says how many words the braces should surround.
-- 
2.20.1.142.g77556354bb