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            • *sbitset-block-size*
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    • Sbitset-pairp

    *sbitset-block-size*

    Size of each block in an sparse bitset.

    The block size can be any positive number, but for good performance you probably want to use the maximal number such that:

    (fixnump (1- (expt 2 *sbitset-block-size*))) = T

    On CCL and SBCL, 60 is the right number. For other Lisps, 60 is logically fine, but other numbers may give you better performance.

    Note: if you change this, you may wish to also write a corresponding, optimized version of sbitset-pair-members.