diff --git a/web/CXM_common.anubis b/web/CXM_common.anubis
index ed03f7c..3e4b173 100644
--- a/web/CXM_common.anubis
+++ b/web/CXM_common.anubis
@@ -47,6 +47,20 @@ public define Maybe(String)
   }
 .
 
+public define String
+  http_header_value
+  (
+    List(HTTP_header) l,
+    String            name,
+    String            default
+  )=
+  if http_header_value(l, name) is
+  {
+    failure         then  default,
+    success(result) then result
+  }
+.
+
 public define List(String)
   to_List_String
   (
--
libgit2 0.21.4