-- in.cue --
intIndex:    [2][0]
stringIndex: {foo: "bar"}["foo"]

stringOfNumberIndex: {"3": 3}["3"]

indexToDefault:        (*[0] | {})[0]
outOfBoundsDisjunction: (*[] | {})[1]

// Ensure these are errors.
indexDoesNotDistribute:     (*[] | [1])[0]
doesNotDistributeType: {
    l: []
    a: (*l | {"3": 3})["3"]
}

stringIndexToList: [2][""]
indexOutOfBounds2: 2[2]
booleanIndex: [][true]
indexOutOfBounds3: [1, 2, 3][4]
negativeIndex: [1, 2, 3][-1]

varIndexTooLarge: {
    n: 3
    a: [1, 2, 3][n]
}

varNegativeIndex: {
    n: -1
    a: [1, 2, 3][n]
}
-- out/eval --
Errors:
outOfBoundsDisjunction: invalid list index 1 (out of bounds):
    ./in.cue:7:36
indexDoesNotDistribute: index out of range [0] with length 0:
    ./in.cue:10:41
doesNotDistributeType.a: invalid list index "3" (type string):
    ./in.cue:13:24
stringIndexToList: invalid list index "" (type string):
    ./in.cue:16:24
indexOutOfBounds2: invalid operand 2 (found int, want list or struct):
    ./in.cue:17:20
booleanIndex: invalid index true (invalid type bool):
    ./in.cue:18:15
    ./in.cue:18:18
indexOutOfBounds3: invalid list index 4 (out of bounds):
    ./in.cue:19:30
negativeIndex: invalid index -1 (index must be non-negative):
    ./in.cue:20:16
    ./in.cue:20:26
varIndexTooLarge.a: index out of range [3] with length 3:
    ./in.cue:24:18
varNegativeIndex.a: index n out of range [-1]:
    ./in.cue:29:8
    ./in.cue:28:8
    ./in.cue:29:18

Result:
(_|_){
  // [eval]
  intIndex: (int){ 2 }
  stringIndex: (string){ "bar" }
  stringOfNumberIndex: (int){ 3 }
  indexToDefault: (int){ 0 }
  outOfBoundsDisjunction: (_|_){
    // [eval] outOfBoundsDisjunction: invalid list index 1 (out of bounds):
    //     ./in.cue:7:36
  }
  indexDoesNotDistribute: (_|_){
    // [eval] indexDoesNotDistribute: index out of range [0] with length 0:
    //     ./in.cue:10:41
  }
  doesNotDistributeType: (_|_){
    // [eval]
    l: (#list){
    }
    a: (_|_){
      // [eval] doesNotDistributeType.a: invalid list index "3" (type string):
      //     ./in.cue:13:24
    }
  }
  stringIndexToList: (_|_){
    // [eval] stringIndexToList: invalid list index "" (type string):
    //     ./in.cue:16:24
  }
  indexOutOfBounds2: (_|_){
    // [eval] indexOutOfBounds2: invalid operand 2 (found int, want list or struct):
    //     ./in.cue:17:20
  }
  booleanIndex: (_|_){
    // [eval] booleanIndex: invalid index true (invalid type bool):
    //     ./in.cue:18:15
    //     ./in.cue:18:18
  }
  indexOutOfBounds3: (_|_){
    // [eval] indexOutOfBounds3: invalid list index 4 (out of bounds):
    //     ./in.cue:19:30
  }
  negativeIndex: (_|_){
    // [eval] negativeIndex: invalid index -1 (index must be non-negative):
    //     ./in.cue:20:16
    //     ./in.cue:20:26
  }
  varIndexTooLarge: (_|_){
    // [eval]
    n: (int){ 3 }
    a: (_|_){
      // [eval] varIndexTooLarge.a: index out of range [3] with length 3:
      //     ./in.cue:24:18
    }
  }
  varNegativeIndex: (_|_){
    // [eval]
    n: (int){ -1 }
    a: (_|_){
      // [eval] varNegativeIndex.a: index n out of range [-1]:
      //     ./in.cue:29:8
      //     ./in.cue:28:8
      //     ./in.cue:29:18
    }
  }
}
-- out/compile --
--- in.cue
{
  intIndex: [
    2,
  ][0]
  stringIndex: {
    foo: "bar"
  }["foo"]
  stringOfNumberIndex: {
    "3": 3
  }["3"]
  indexToDefault: (*[
    0,
  ]|{})[0]
  outOfBoundsDisjunction: (*[]|{})[1]
  indexDoesNotDistribute: (*[]|[
    1,
  ])[0]
  doesNotDistributeType: {
    l: []
    a: (*〈0;l〉|{
      "3": 3
    })["3"]
  }
  stringIndexToList: [
    2,
  ][""]
  indexOutOfBounds2: 2[2]
  booleanIndex: [][true]
  indexOutOfBounds3: [
    1,
    2,
    3,
  ][4]
  negativeIndex: [
    1,
    2,
    3,
  ][-1]
  varIndexTooLarge: {
    n: 3
    a: [
      1,
      2,
      3,
    ][〈0;n〉]
  }
  varNegativeIndex: {
    n: -1
    a: [
      1,
      2,
      3,
    ][〈0;n〉]
  }
}