quicksort implementation in jq

qsort.jq

def partition($p): 
{
    "less": (. | map(select(. < $p))),
    "equal": (. | map(select(. == $p))),
    "greater": (. | map(select(. > $p)))
};

def qsort:
(
    if (. | length | . <= 1) then . else
        partition(.[0]) |
        [
            (.less|qsort|.[]),
            (.equal|.[]),
            (.greater|qsort|.[])
        ]
    end
);

. | qsort