--- a/src/luan/modules/BasicLuan.java	Sun Jan 13 17:14:45 2019 -0700
+++ b/src/luan/modules/BasicLuan.java	Sun Jan 13 17:28:57 2019 -0700
@@ -228,8 +228,15 @@
 		}
 	}
 
-	public static String stringify(Object obj,Boolean strict) throws LuanException {
-		boolean b = strict!=null ? strict : false;
+	public static String stringify(Object obj,String strict) throws LuanException {
+		boolean b;
+		if( strict==null ) {
+			b = false;
+		} else if( strict.equals("strict") ) {
+			b = true;
+		} else {
+			throw new LuanException("strict must be nil or 'strict'");
+		}
 		return LuanToString.toString(obj,b);
 	}