Actually it is more subtle than even that. You can't replace !1 with 0 nor with "".

0 is wrong because, in a string context, !1 is "" while 0 is "0".

"" is wrong because, when warnings are turned on, 0+"" generates q(Argument "" isn't numeric) while 0+!1 is silent.

        - tye (but my friends call me "Tye")

In reply to (tye)Re: I've never seen this syntax before by tye
in thread I've never seen this syntax before by ChuckularOne

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