Hi friends, I have a nested list that is unstructured, and I really know how much it has nested list or map in itself.

I just need to search and get all :tag key in this list and check the selected name by my user exists there or it is unique.

For example:

[
  %{
    children: [
      %{
        children: [],
        id: "fcfb1066-6e16-4a84-81e0-7746f12b7e76",
        tag: "test1",
        type: "section"
      },
      %{
        id: "035ca737-2cc2-488b-83f5-fe7cc2becc5e",
        parent_id: "a9963499-f6a4-4a32-bafa-aa22a9b059bc",
      },
      %{
        children: [
          %{
            other: [
              %{
                id: "035ca737-2cc2-488b-83f5-fe7cc2becc5e",
                parent_id: "a9963499-f6a4-4a32-bafa-aa22a9b059bc",
              },
            ],
            tag: "test4",
          },
        ],
        id: "8a9f0126-33a0-4c03-8c4a-5507f0562c8a",
        index: 2,
        parent: "layout",
        parent_id: "a9963499-f6a4-4a32-bafa-aa22a9b059bc",
        tag: "test2",
        type: "section"
      }
    ],
    parent: "dragLocation",
    parent_id: "dragLocation",
    tag: "test3",
  }
]

This list has no a structure that helps me to use Enum.

So I try to use macro, but based on my little knowledge I could not to find all :tag, see this code please

defmacro get_tags(data, selected_name) do
  quote do
    data = unquote(data)
    data_string = inspect(data, charlists: :as_strings)
    ast = Code.string_to_quoted(data_string)
    
    ....
  end
end

the ast = Code.string_to_quoted(data_string) passes me a nested list again, and I don’t know how to create a pattern to get tag, so after that I use to List.flatten ast but I got this error:
** (FunctionClauseError) no function clause matching in :lists.flatten/1

because It has maps in its list

Please help me to learn more about macro and search like this in a list, Thank you in advance.