How to apply toString() to a large list of documents?

[vnugent]

I encounter of several instances where I need to convert an array of sub-documents with MUUID fields to string. If the list is small, I can loop through the array and call toUUID().toString() on each MUUID field. But when the array is large or nested, how would you apply toString() efficiently?

[{
  "name": "mary"
  "books": [
    {
      "id": "MUUID_type"
      "title": "War and Peace"
    }
  ]
}]

[cdimascio]

for more context, can you provide a small code snippet given the scenario you're grappling with. additionally, how would you expect the solution to work