interface A
  integer x
endinterface

struct B extends A
  integer y
endstruct

struct C extends A
  integer y
  integer z
endstruct

function test takes A inst returns nothing
  local A aaa = 0

  if (inst.getType() == C.typeid) then
    set aaa = C.create()
    set C(aaa).z = 3

  elseif (inst.getType() == B.typeid) then
    set aaa = B.create()
    set B(aaa).y = 2
  endif

endfunction