Reader hacks, whitespace algorithm

[Rem@IMSSS]

It doesn't matter if your algorithm is inefficient, because it has
to be run only once per different character, after which the results
can be kept in a lookup table or as properties hanging off the character
objects. Therefore if the algorithm works at all, I think you have
solved the problem at hand, and since it's portable there's no urgency
to put your algorithm in the CLtL manual, the yellow pages will suffice.
<opinion of REM>
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