How to use jq to output JSONL (one independent JSON object per line)

Question

My request sounds trivial but I could not find a way to do it. I have as input an array of JSON objects:

[
    {
        \"foo\": 1,
        \"bar\": 2
    }         


        

Answer 1

Found: it's

map(tostring) | reduce .[] as $item (""; . + $item + "\n")

You also need to use --raw-output.

Answer 2

The answer to the original question is to use the filter .[] together with the -c command-line option:

$ jq -c '.[]'

Answer 3

If the input array is too large to fit into memory, you can use jq's so-called "streaming parser".

Here is an illustration using a generic approach, that is, it makes no assumptions about the items in the top-level array:

$ echo '[{"foo":"bar"},99,null,{"foo":"baz"}]' |
  jq -cn --stream 'fromstream( inputs|(.[0] |= .[1:]) | select(. != [[]]) )'
{"foo":"bar"}
99
null
{"foo":"baz"}
$