diff --git a/minproto.leg b/minproto.leg
index b4a41eb..041fa26 100644
--- a/minproto.leg
+++ b/minproto.leg
@@ -2677,8 +2677,8 @@ oop newForFromTo(oop identifier, oop first, oop last, oop body)
 oop ForFromTo_eval(oop exp, oop env)
 {
     oop identifier = Object_get(exp, sym_identifier);
-    oop first      = Object_get(exp, sym_first);
-    oop last       = Object_get(exp, sym_last);
+    oop first      = eval(Object_get(exp, sym_first), env);
+    oop last       = eval(Object_get(exp, sym_last), env);
     oop body       = Object_get(exp, sym_body);
     oop env2       = new(pObject);
     _setDelegate(env2, env);