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in reply to Re^3: The mystery of double negation (bool 0)
in thread The mystery of double bitwise negation

Interestingly, !1 is "", ~~(!1) is 0, but ~~("") is "". 
$ perl -MO=Deparse -E'say !1; say ~~(!1); say ~~("");'
use feature 'current_sub', 'evalbytes', 'fc', 'say', 'state', 'switch'
+, 'unicode_strings', 'unicode_eval';
say !1;
say 0;
say '';
-e syntax OK

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