docs(xml): document the tree function

1 files changed, 2 insertions, 0 deletions

diff --git a/lib/xml.ml b/lib/xml.ml
index c73bad6..1b286bb 100644
--- a/lib/xml.ml
+++ b/lib/xml.ml
@@ -8,6 +8,8 @@ type element = {
   }
 
 let tree s : element option =
+  (** [tree s] is an [element option] representing the XML element inside of stream [s],
+      if [s] is a complete element from start to end. *)
   let element (namespace, name) attributes children =
     Either.Left {
         namespace;