From: Richard M. Stallman <rms@gnu.org>
Date: Sat, 9 Jul 2005 03:42:43 +0000 (+0000)
Subject: (Fdefvar): Allow defvaring a constant to itself quoted.
X-Git-Tag: emacs-pretest-22.0.90~8271
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=ed6cefb42c8847289ff83bf43b5370d878c93697;p=emacs.git

(Fdefvar): Allow defvaring a constant to itself quoted.
---

diff --git a/src/eval.c b/src/eval.c
index f625258229e..45effae295c 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -807,8 +807,16 @@ usage: (defvar SYMBOL &optional INITVALUE DOCSTRING)  */)
 
   sym = Fcar (args);
   if (SYMBOL_CONSTANT_P (sym))
-    error ("Constant symbol `%s' specified in defvar",
-           SDATA (SYMBOL_NAME (sym)));
+    {
+      /* For updward compatibility, allow (defvar :foo (quote :foo)).  */
+      tem = Fcar (Fcdr (args));
+      if (! (CONSP (tem)
+	     && EQ (XCAR (tem), Qquote)
+	     && CONSP (XCDR (tem))
+	     && EQ (XCAR (XCDR (tem)), sym)))
+	error ("Constant symbol `%s' specified in defvar",
+	       SDATA (SYMBOL_NAME (sym)));
+    }
 
   tail = Fcdr (args);
   if (!NILP (Fcdr (Fcdr (tail))))