diff --git a/src/traverse/estraverse b/src/traverse/estraverse
index 2c900e4..dbae6c1 100644
--- a/src/traverse/estraverse
+++ b/src/traverse/estraverse
@@ -23,7 +23,7 @@
   THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 
-let Syntax, VisitorKeys, BREAK, SKIP, REMOVE
+let Syntax, VisitorKeys, BREAK, SKIP, REMOVE, VisitorOption
 
 Syntax = {
   AssignmentExpression: "AssignmentExpression",