diff --git a/peg.el b/peg.el
index 0e4221eeb7..fa7e23619f 100644
--- a/peg.el
+++ b/peg.el
@@ -314,10 +314,14 @@ RULES is a list of rules of the form (NAME . PEXS), where PEXS is a sequence
 of PEG expressions, implicitly combined with `and'."
   (declare (indent 1) (debug (sexp form))) ;FIXME: `sexp' is not good enough!
   (let ((rules
-         ;; First, macroexpand the rules.
-         (mapcar (lambda (rule)
-                   (cons (car rule) (peg-normalize `(and . ,(cdr rule)))))
-                 rules))
+	 (progn
+	   ;; Handle RULES as a variable.
+	   (when (symbolp rules)
+	     (setq rules (symbol-value rules)))
+           ;; Then macroexpand the rules.
+           (mapcar (lambda (rule)
+                     (cons (car rule) (peg-normalize `(and . ,(cdr rule)))))
+                   rules)))
         (ctx (assq :peg-rules macroexpand-all-environment)))
     (macroexpand-all
      `(cl-labels