If I haven’t overlooked the explanation (I have read only part of it and skimmed the rest), my guess for the non-membership definition of the empty string would be all the SQL and programming queries where “” stands for matching all elements (or sometimes matching none). The small round things are a riddle for me too.
If I haven’t overlooked the explanation (I have read only part of it and skimmed the rest), my guess for the non-membership definition of the empty string would be all the SQL and programming queries where “” stands for matching all elements (or sometimes matching none). The small round things are a riddle for me too.