Issue with recursive iteration and arrays

[CJCombrink]

I am trying to recursively iterate a JSON Object but seem to have issues with an array.

I have code sort of based on this code on Stack Overflow: https://stackoverflow.com/a/73323420/991000
I started with the code posted on the same question from @nlohmann but I need the full paths (json_pointers) to the elements.

The issue is that inside the recursive function when I call it.key I get the following runtime exception:

terminate called after throwing an instance of 'nlohmann::json_v3_11_1::detail::invalid_iterator'
  what():  [json.exception.invalid_iterator.207] cannot use key() for non-object iterators
Program terminated with signal: SIGSEGV

From my understanding from the docs the it.key() function is supposed to give me the array index, from the note:

When iterating over an array, key() will return the index of the element as string. For primitive types (e.g., numbers), key() returns an empty string.

See my example on compiler explorer: https://godbolt.org/z/Yr8jdhqoc

Am I doing anything wrong or how would I get this to work as expected.
Or is this a bug?

I am using nlohmann_json/3.11.2

[nomadwolf0]

It looks like only the iterators into the collection returned by basic_json::items() supports that use of it.key(). The regular iterators of basic_json do not have this feature. Not sure if that's intentional, but that's what seems to be currently implemented.

[nomadwolf0]

Slightly uglier than what I had hoped, but here's a working version iterating over items(): https://godbolt.org/z/vfvWq6e4x