diff --git a/web/CXM_web_arg_utils.anubis b/web/CXM_web_arg_utils.anubis
index 4b0a285..832b813 100644
--- a/web/CXM_web_arg_utils.anubis
+++ b/web/CXM_web_arg_utils.anubis
@@ -129,6 +129,18 @@ public define Maybe(String)
   }
 .
 
+public define Maybe(Bool)
+  get_mb_Bool
+  (
+    List(Web_arg) lwa,
+    String        arg_name
+  ) =
+  if web_arg_value(lwa, arg_name) is
+  {
+    not_found     then failure,
+    found(value)  then success(to_Bool(value))
+  }.
+  
 public define Bool
   get_Bool
   (
@@ -137,8 +149,8 @@ public define Bool
   ) =
   if web_arg_value(lwa, arg_name) is
   {
-    not_found then false,
-    found(_)  then true
+    not_found     then false,
+    found(value)  then true
   }.
 
 public define Bool
--
libgit2 0.21.4