map-inverted-index maps a function of two variables, taking key and instance, over a subset of class instances in the order defined by the index. Specify the class by classname or class object and index by quoted name. The index may be a slot index, derived index, or a valued association slot.
To map only a subset of key-value pairs, specify the range using the :start and :end keywords; all elements greater than or equal to :start and less than or equal to :end will be traversed regardless of whether the start or end value is in the index.
Use nil in the place of start or end to specify the first element or last element, respectively.
To map a single value, iff it exists, use the :value keyword. This is the only way to travers all nil values.
To map from :end to :start in descending order, set :from-end to true. If :value is used, :from-end is ignored
The 'oids' argument passes the oid of the instance to the provided function instead of the recreated instance.