@value interface Type1 {}

@value interface Type2 {
  refines Type1
}

@value interface Type3 {
  refines Type2
}

@value interface Interface1 {
  something (Type2) -> (Type1)
}

@value interface Interface2 {
  something (Type3) -> (Type2)
}

@value interface Parent {
  refines Interface1
  refines Interface2

  something (Type2) -> (Type2)
}

concrete Child {
  refines Parent
}