-- in.cue --
t1: {
	#R: {
		pos:  uint
		name: "hello_\(pos)"
	}
	a: #R & {pos: 67}
}
t2: {
	#R: {
		pos:  string
		name: "hello_\(pos)"
	}
	a: #R & {pos: "a"}
}
-- out/eval --
(struct){
  t1: (struct){
    #R: (#struct){
      pos: (int){ &(>=0, int) }
      name: (_|_){
        // [incomplete] t1.#R.name: invalid interpolation: non-concrete value >=0 & int (type int):
        //     ./in.cue:4:9
      }
    }
    a: (#struct){
      pos: (int){ 67 }
      name: (string){ "hello_67" }
    }
  }
  t2: (struct){
    #R: (#struct){
      pos: (string){ string }
      name: (_|_){
        // [incomplete] t2.#R.name: invalid interpolation: non-concrete value string (type string):
        //     ./in.cue:11:9
      }
    }
    a: (#struct){
      pos: (string){ "a" }
      name: (string){ "hello_a" }
    }
  }
}
-- out/compile --
--- in.cue
{
  t1: {
    #R: {
      pos: &(int, >=0)
      name: "hello_\(〈0;pos〉)"
    }
    a: (〈0;#R〉 & {
      pos: 67
    })
  }
  t2: {
    #R: {
      pos: string
      name: "hello_\(〈0;pos〉)"
    }
    a: (〈0;#R〉 & {
      pos: "a"
    })
  }
}