gnus-util.el (gnus-macroexpand-all): Allow optional argument `environment'.

lisp/gnus/ChangeLog

 2010-12-03  Katsumi Yamaoka  <yamaoka@jpl.org>
-	* gnus-util.el (gnus-macroexpand-all): Don't modify argument.
+	* gnus-util.el (gnus-macroexpand-all): Don't modify argument;
+	allow optional argument `environment'.
 2010-12-03  Glenn Morris  <rgm@gnu.org>

lisp/gnus/gnus-util.el

@@ -2036,9 +2036,11 @@ Same as `string-match' except this function does not change the match data."
 
 (if (fboundp 'macroexpand-all)
     (defalias 'gnus-macroexpand-all 'macroexpand-all)
-  (defun gnus-macroexpand-all (form)
+  (defun gnus-macroexpand-all (form &optional environment)
     "Return result of expanding macros at all levels in FORM.
-If no macros are expanded, FORM is returned unchanged."
+If no macros are expanded, FORM is returned unchanged.
+The second optional arg ENVIRONMENT specifies an environment of macro
+definitions to shadow the loaded ones for use in file byte-compilation."
     (if (consp form)
 	(let ((idx 1)
 	      (len (length (setq form (copy-sequence form))))
@@ -2046,7 +2048,7 @@ If no macros are expanded, FORM is returned unchanged."
 	  (while (< idx len)
 	    (setcar (nthcdr idx form) (gnus-macroexpand-all (nth idx form)))
 	    (setq idx (1+ idx)))
-	  (if (eq (setq expanded (macroexpand form)) form)
+	  (if (eq (setq expanded (macroexpand form environment)) form)
 	      form
 	    (gnus-macroexpand-all expanded)))
       form)))