fn gen{T}(a:T) : u8 = tupsel{0,a}

fn fun() = {
  x:tup{u8,i32} = tup{4, 1}
  y := gen{tup{u8,i32}}(x)
  z := gen{tup{u8,type{x}}}(tup{y,x})
       gen{tup{u8}}(tup{z})
}