diff --git a/modhex.go b/modhex.go
index 0ae17bd..269ebdb 100644
--- a/modhex.go
+++ b/modhex.go
@@ -10,6 +10,7 @@ import (
 // modhex character table for encoding
 const modhexTable = "cbdefghijklnrtuv"
 
+// modhex map for decoding
 var modhexMap map[byte]byte
 
 func init() {