Method Dispatch for Multi-Method Object-Oriented Languages

Two new techniques for multi-method dispatch are presented, both sufficiently general to apply to reflexive languages where methods and types can be added and removed at run-time. However, these techniques also apply to non-reflexive languages. One of the techniques operates by performing projections onto single-receiver dispatch tables, and thus benefits from existing research into single-receiver dispatch techniques. It provides method dispatch in O(k), where k is the arity of the method, and it is up to 6 times more space efficient than current table-based techniques. The second new technique does not provide constant-time dispatch, but has very low memory requirements and performs favorably against other techniques at a large percentage of call-sites. It is meant to be used as a replacement for inheritance lookup as the cache-miss algorithm in existing cache-based techniques.