v4, alpha 6 (#17)

Reviewed-on: #17

src/Htmx/Htmx.fs

@@ -24,6 +24,7 @@ type IHeaderDictionary with
         with get () = hdr this "HX-History-Restore-Request" |> Option.map bool.Parse
     
     /// <summary>The user response to an <c>hx-prompt</c></summary>
+    [<Obsolete "hx-prompt is removed in v4">]
     member this.HxPrompt
         with get () = hdr this "HX-Prompt"
 
@@ -31,15 +32,29 @@ type IHeaderDictionary with
     member this.HxRequest
         with get () = hdr this "HX-Request" |> Option.map bool.Parse
 
+    /// <summary>The tag name (fst) and <c>id</c> attribute (snd) of the element triggering this request</summary>
+    member this.HxSource
+        with get () =
+            match hdr this "HX-Source" with
+            | Some src ->
+                let parts = src.Split "#"
+                if parts.Length = 1 then
+                    Some (parts[0], None)
+                else
+                    Some (parts[0], if parts[1] <> "" then Some parts[1] else None)
+            | None -> None
+
     /// <summary>The <c>id</c> attribute of the target element if it exists</summary>
     member this.HxTarget
         with get () = hdr this "HX-Target"
 
     /// <summary>The <c>id</c> attribute of the triggered element if it exists</summary>
+    [<Obsolete "HX-Trigger is removed in v4; use the second item of HX-Source">]
     member this.HxTrigger
         with get () = hdr this "HX-Trigger"
 
     /// <summary>The <c>name</c> attribute of the triggered element if it exists</summary>
+    [<Obsolete "HX-Trigger-Name is removed in v4; may be available via extension, but will be removed from this library">]
     member this.HxTriggerName
         with get () = hdr this "HX-Trigger-Name"