Companion

A slot to hold the cached hash value of a tuple. If zero, then the hash value must be computed upon request. Note that in the very rare case that the hash value actually equals zero, the hash value has to be computed every time it is requested.

The number of elements in this subrange tuple, starting at the START_INDEX. Must not be zero, and should probably be at least some reasonable size to avoid time and space overhead.

The first index of the basis tuple that is within this subrange.