trait HtmlHelpers { protected def css(src:String) = <link href={src} media="screen" rel="stylesheet" type="text/css" /> } trait BlueprintHelpers { // this line does the magic this: HtmlHelpers => def screen:Elem = css("blueprint/screen.css") def ie:Node = <!--[if lt IE 8]><link rel="stylesheet" href="/css/blueprint/ie.css" type="text/css" media="screen, projection" /><![endif]--> }