compare_usage1(urdo, ucur)urdo or ucur is NULL
or NA, the list contains only the fields "obj_removed", "obj_added",
"rdo_usage", "cur_usage", and "alias".urdo to the usage inferred from the actual definitions of the
functions. The comparison is symmetric but the interpretation assumes
that ucur may be more recent. Note: do not compare the return value to TRUE with identical or
isTRUE. The attribute makes the returned value not identical to
TRUE in any case.
inspect_usage