Problem when using Reference with regexp

[gulnarrra]

Hi,
I have a json-file with two structures inside. And depending on data in one structure I validate data in the second one.
Without regexp all works as expected. But with regexp I have a problem and need help)

Validation task description:
If description.someapp.level1.folder.aaa exists, I check existence of object_aaa in list: "/tmp/content-1.yml".structure.xyz.list1. If object_aaa does not exist, error will be raised for user: "ERROR: object_aaa does not exist".

Expected test results:

"folder" element	List object	Name	Test
+	+	aaa	test ok
+	-	bbb	test fail
-	-	ccc	test ok (don't check because no "ccc" element inside "folder" structure)

Example (success):
data.json:

{
  "/tmp/content-1.yml": {
    "structure": {
      "foo": "bar",
      "xyz": {
        "list1": [
          "object_aaa",
          "not_object_bbb",
          "not_object_ccc"
        ]
      }
    }
  },
  "description": {
    "someapp": {
      "level1": {
        "folder": {
          "aaa": {"qwe": "rty"},
          "bbb": {"1": "2"},
          "not_ccc": {"how-much-is-the-fish": "42"}
        }
      }
    }
  }
}

noregexp_check_rules.cue:

package cue_rules
import "list"
{
  ...
  description?: {
    someapp?: {
      level1?: {
        folder?: {
          aaa?: {...},
          bbb?: {...},
          ccc?: {...}
        }
      }
    }
  }
  ["/tmp/content-1.yml"]: "structure"?: {
    ...
    "xyz"!: {
      list1="list1"!: [...]
      ...
      if description.someapp.level1.folder.aaa != null {
        "ERROR: object_aaa does not exist": list.Contains(list1,"object_aaa") & true
      }
      if description.someapp.level1.folder.bbb != null {
        "ERROR: object_bbb does not exist": list.Contains(list1,"object_bbb") & true
      }
      if description.someapp.level1.folder.ccc != null {
        "ERROR: object_ccc does not exist": list.Contains(list1,"object_ccc") & true
      }
    }
  }
}

All works fine:

$ cue vet data.json noregexp_check_rules.cue
"/tmp/content-1.yml".structure.xyz."ERROR: object_bbb does not exist": conflicting values true and false:
    ./noregexp_check_rules.cue:6:1
    ./noregexp_check_rules.cue:20:27
    ./noregexp_check_rules.cue:28:7
    ./noregexp_check_rules.cue:29:45
    ./noregexp_check_rules.cue:29:81

But if I want to use instead of "someapp" something like "qwerty-123.456-app" or "asdfgh-000.111-app" , I have to use regex: ".+app".

withregexp_check_rules.cue:

package cue_rules
import "list"
{
  ...
  description?: {
    ".+app"?: {
      level1?: {
        folder?: {
          aaa?: {...},
          bbb?: {...},
          ccc?: {...}
        }
      }
    }
  }

  ["/tmp/content-1.yml"]: "structure"?: {
    ...
    "xyz"!: {
      list1="list1"!: [...]
      ...
      if ("description..+app.level1.folder.aaa") != null {
        "ERROR: object_aaa does not exist": list.Contains(list1,"object_aaa") & true
      }
      if ("description..+app.level1.folder.bbb") != null {
        "ERROR: object_bbb does not exist": list.Contains(list1,"object_bbb") & true
      }
      if ("description..+app.level1.folder.ccc") != null {
        "ERROR: object_ccc does not exist": list.Contains(list1,"object_ccc") & true
      }
    }
  }
}

Here "if" statements not working correct:

$ cue vet data.json withregexp_check_rules.cue
"/tmp/content-1.yml".structure.xyz."ERROR: object_bbb does not exist": conflicting values true and false:
    ./withregexp_check_rules.cue:5:1
    ./withregexp_check_rules.cue:19:27
    ./withregexp_check_rules.cue:27:7
    ./withregexp_check_rules.cue:28:45
    ./withregexp_check_rules.cue:28:81
"/tmp/content-1.yml".structure.xyz."ERROR: object_ccc does not exist": conflicting values true and false:
    ./withregexp_check_rules.cue:5:1
    ./withregexp_check_rules.cue:19:27
    ./withregexp_check_rules.cue:30:7
    ./withregexp_check_rules.cue:31:45
    ./withregexp_check_rules.cue:31:81

I suppose the raison is that cue interprets ("description..+app.level1.folder.ccc") statement as a string.
I tried to use alias for regexp inside "description" scope, but I got error: "description: unreferenced alias or let clause".

Question: how I can reference ".+app" regexp from "description" scope inside of "/tmp/content-1.yml".structure.xyz.list scope? How to correctly write "if" statement?