bug#26923: 25.2; `setq-local': allow multiple assignments or add optional buffer arg

[Lars Ingebrigtsen <larsi@gnus.org>]

Drew Adams <drew.adams@oracle.com> writes:

> 1. I believe this has been discussed before, and presumably the result
>    (decision or lack of one) has been not to make the change, but I'd
>    still suggest that `setq-local', like `setq', should allow multiple
>    assignment pairs.

This was implemented by

Jordon Biondo <jordonbiondo@gmail.com>

but never applied.  Biondo has copyright assignment papers on file, but
apparently the final movement here was this email from Eli:

> > From: Jordon Biondo <jordonbiondo@gmail.com>
> > Date: Wed, 8 Feb 2017 10:59:19 -0500
> > Cc: John Wiegley <jwiegley@gmail.com>, Emacs development discussions
> > <emacs-devel@gnu.org>
> > 
> > My paperwork is now complete, if that's the only thing holding up this patch.
>
> Thanks.  Could you please re-submit your patch, and add to it suitable
> changes to NEWS and to the ELisp manual?

Eli, if you still think this is something that should be done, I can add
the NEWS entry and the manual changes.  I've re-spun the patch for the
current trunk:

diff --git a/lisp/subr.el b/lisp/subr.el
index e361b8324f..8cb8bcef69 100644
--- a/lisp/subr.el
+++ b/lisp/subr.el
@@ -143,11 +143,22 @@ setq-default
       (push `(set-default ',(pop args) ,(pop args)) exps))
     `(progn . ,(nreverse exps))))
 
-(defmacro setq-local (var val)
-  "Set variable VAR to value VAL in current buffer."
+(defmacro setq-local (&rest args)
+  "Set each SYM to the value of its VAL in the current buffer.
+
+\(fn [SYM VAL]...)"
   ;; Can't use backquote here, it's too early in the bootstrap.
   (declare (debug (symbolp form)))
-  (list 'set (list 'make-local-variable (list 'quote var)) val))
+  (let ((expr))
+    (while args
+      (setq expr
+            (cons
+             (list 'set
+                   (list 'make-local-variable (list 'quote (car args)))
+                   (car (cdr args)))
+             expr))
+      (setq args (cdr (cdr args))))
+    (cons 'progn (nreverse expr))))
 
 (defmacro defvar-local (var val &optional docstring)
   "Define VAR as a buffer-local variable with default value VAL.


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