-- in.cue --
{
  #a: {b: 2.0, s: "abc"}
  b: #a.b
  c: #a.c
  d: #a["d"]
  e: #a.t[2:3]
}
-- out/def --
#a: {
	b: 2.0
	s: "abc"
}
b: 2.0
c: _|_ // undefined field "c"
d: _|_ // undefined field "d"
e: _|_ // undefined field "t"
-- out/compile --
--- in.cue
{
  {
    #a: {
      b: 2.0
      s: "abc"
    }
    b: 〈0;#a〉.b
    c: 〈0;#a〉.c
    d: 〈0;#a〉["d"]
    e: 〈0;#a〉.t[2:3]
  }
}
-- out/eval --
Errors:
c: undefined field c:
    ./in.cue:4:9
d: undefined field d:
    ./in.cue:5:9
e: undefined field t:
    ./in.cue:6:9

Result:
(_|_){
  // [eval]
  #a: (#struct){
    b: (float){ 2.0 }
    s: (string){ "abc" }
  }
  b: (float){ 2.0 }
  c: (_|_){
    // [eval] c: undefined field c:
    //     ./in.cue:4:9
  }
  d: (_|_){
    // [eval] d: undefined field d:
    //     ./in.cue:5:9
  }
  e: (_|_){
    // [eval] e: undefined field t:
    //     ./in.cue:6:9
  }
}