Any JQ built-in function returning index of element in JSON array?

Question

I have created a csv output from an input JSON file.

Since some JSON arrays do not have their own id's, I need to add a unique id in my csv output that will be based on index of current element in its JSON array.

Is there any built-in JQ function returning the element index?

Answer 1

to_entries should work perfectly.

jq -n '["a","b","c"] | to_entries'

will produce

[{"key":0,"value":"a"},{"key":1,"value":"b"},{"key":2,"value":"c"}]