Some serious bug-fix work to get HTML example to compile; this includes fixing a bug with 'val' patterns in Unnest and the need for more local reduction in Especialize

fun main () : transaction page =
    let
        val x = 1
        val y = "Hello"
        val z = 3.45
    in
        return <xml>{[x]}, {[y]}, {[z]}</xml>
    end