From 23e67294ec391d1456a6bd25c9793446abb32aee Mon Sep 17 00:00:00 2001
From: Justin Ethier <justin.ethier@gmail.com>
Date: Thu, 7 Dec 2017 12:41:03 -0500
Subject: [PATCH] Handle renamed syntax-rules when expanding define-syntax

---
 scheme/eval.sld |  2 +-
 tests/when.scm  | 16 ++++++++--------
 2 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/scheme/eval.sld b/scheme/eval.sld
index 761d4bfd..4474322a 100644
--- a/scheme/eval.sld
+++ b/scheme/eval.sld
@@ -887,7 +887,7 @@
             (trans (caddr exp))
             (body (cadr trans)))
        (cond
-        ((tagged-list? 'syntax-rules trans) ;; TODO: what if syntax-rules is renamed?
+        ((macro:syntax-rules? (env:lookup (car trans) env #f)) ;; Handles renamed 'syntax-rules' identifier
          (_expand
            `(define-syntax ,name ,(_expand trans env rename-env local-env))
            env rename-env local-env))
diff --git a/tests/when.scm b/tests/when.scm
index d210cb2f..c24cbf20 100644
--- a/tests/when.scm
+++ b/tests/when.scm
@@ -4,14 +4,14 @@
 ;    ((my-when test result1 result2 ...)
 ;     (if test
 ;         (begin result1 result2 ...)))))
-;
-;(define-syntax my-when2
-;  (syntax-rules ()
-;    ((my-when test result1 result2 ...)
-;     (list result2 ...))))
-;
-;;(write
-;;  (my-when2 #t 1))
+
+(define-syntax my-when2
+  (syntax-rules ()
+    ((my-when test result1 result2 ...)
+     (list result2 ...))))
+
+(write
+  (my-when2 #t 1))
 ;
 ; (define my-when2*
 ;   (lambda (expr$28 rename$29 compare$30)