Construct an outpack query, typically then passed through to outpack_search
outpack_query(expr, name = NULL, scope = NULL, subquery = NULL)The query expression
Optionally, the name of the packet to scope the query on. This
will be intersected with scope arg and is a shorthand way of running
scope = list(name = "name")
Optionally, a scope query to limit the packets
searched by pars
Optionally, named list of subqueries which can be
referenced by name from the expr.
An outpack_query object, which should not be modified,
but which can be passed to outpack_search()