anchor.diff:      member this.RemoveClass'(cls: string) =
           elt?className <-
               (elt?className: String).Replace(
  -                new RegExp(@"(\s|^)" + cls + @"(\s|$)"),
  -                " ")
  +                new RegExp(@"(?:(\s|^)" + cls + @")+(\s|$)", "g"),
  +                "$1")
   
       [<Name "HasClass">]
       member this.HasClass'(cls: string) =
  
positive.code:         As (Doc'.Verbatim' s)
  
  and [<JavaScript; Proxy(typeof<Elt>); Name "WebSharper.UI.Next.Elt">]
      private Elt'(docNode, updates, elt: Dom.Element, rvUpdates: Var<View<unit>>, attrUpdates) =
      inherit Doc'(docNode, updates)
  
      static member internal New(el: Dom.Element, attr: Attr, children: Doc') =
  
negative.code:         let rvUpdates = Var.Create children.Updates
          let attrUpdates = Attrs.Updates node.Attr
          let updates = View.Bind (View.Map2 (fun () () -> ()) attrUpdates) rvUpdates.View
          new Elt'(ElemDoc node, updates, el, rvUpdates)
  
      [<Inline "$0.elt">]
      member this.Element = elt
  