-- in.cue --
out: {
        instance
}
instance: #Type & {
        alpha: bravo: charlie: true
}
#Type: #Root & {
        alpha?: bravo?: charlie?: bool
}
#Root: { ... }
-- out/eval --
(struct){
  out: (#struct){
    alpha: (#struct){
      bravo: (#struct){
        charlie: (bool){ true }
      }
    }
  }
  instance: (#struct){
    alpha: (#struct){
      bravo: (#struct){
        charlie: (bool){ true }
      }
    }
  }
  #Type: (#struct){
  }
  #Root: (#struct){
  }
}
-- out/compile --
--- in.cue
{
  out: {
    〈1;instance〉
  }
  instance: (〈0;#Type〉 & {
    alpha: {
      bravo: {
        charlie: true
      }
    }
  })
  #Type: (〈0;#Root〉 & {
    alpha?: {
      bravo?: {
        charlie?: bool
      }
    }
  })
  #Root: {
    ...
  }
}