==== VARIATION: query={ a,[]~|-<>: 1 }, sort={}, proj={}
eqa\,\[\]\~\|\-<>@f
==== VARIATION: query={}, sort={ a,[]~|-<>: 1 }, proj={}
an~aa\,\[\]\~\|\-<>@f
==== VARIATION: query={}, sort={}, proj={ a,[]~|-<>: 1 }
an|_id-a\,\[\]\~\|\-<>@f
==== VARIATION: query={}, sort={}, proj={ a: "foo,[]~|-<>" }
an|_id@f
