scala - Shapeless: restricting case class types -

(note: split shapeless: trying restrict hlist elements type , shapeless: own hlist constraint using coproduct )

question 3 - restrict case classes parameter types

a nice additional gain be, if use hlist constraints constrain case class built anyvals, strings, , specific mybasetrait, recursively fulfill same constraint. constraint being defined on base trait , not have touch derived case class great. like:

trait mybasetrait type mycp = boolean :+: long :+: ... :+: string :+: mybasetrait case class validsimple(b: boolean, s: string) extends mybasetrait case class validnested(s: string, vs: validsimple) extends mybasetrait case class notofbasetrait(l: long)  case class invalidnested(s: string, vs: notofbasetrait) extends mybasetrait // => compile error 

this allow fail lot earlier. possible? via generic#repr or deephlist?