Extract currently requires a subexpression like:
["extract", ["foo","bar"]
["null?", "certname", false]]
But the above will always be false, it would be better to just allow an empty subexpression like below:
["extract", ["foo","bar"]]
Ryan Senior It seems that the subexpression can be empty:
["extract", ["foo","bar"] null]
or
["extract", ["foo","bar"] []]
I'm not sure if it's the proper approach though.