list checking fix

1 files changed, 1 insertions, 1 deletions

diff --git a/builtin.h b/builtin.h
index c1a38bd..a01c93e 100644
--- a/builtin.h
+++ b/builtin.h
@@ -6,7 +6,7 @@
 
 using std::string;
 
-
+bool is_list(Cons *ptr);
 
 /** @class InexactNumObj
  * Inexact number implementation (using doubles)