From c74e14cbdb35c30932b00cabdf878422e685a1cc Mon Sep 17 00:00:00 2001
From: Alex Shinn <ashinn@users.noreply.github.com>
Date: Tue, 22 Jul 2014 21:21:44 +0900
Subject: [PATCH] Don't consider undefined bindings as implicit exports.

---
 eval.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/eval.c b/eval.c
index fe4faf29..11bc6621 100644
--- a/eval.c
+++ b/eval.c
@@ -201,7 +201,8 @@ sexp sexp_env_exports_op (sexp ctx, sexp self, sexp_sint_t n, sexp env) {
     sexp_push(ctx, res, sexp_cadr(ls));
 #endif
   for (ls=sexp_env_bindings(env); sexp_pairp(ls); ls=sexp_env_next_cell(ls))
-    sexp_push(ctx, res, sexp_car(ls));
+    if (sexp_env_value(ls) != SEXP_UNDEF)
+      sexp_push(ctx, res, sexp_car(ls));
   sexp_gc_release1(ctx);
   return res;
 }