perl -Mdiagnostics -e 'print "hello" if "0"' also give some extra hints, although nothing specific. I am lead to believe that perl perhaps fails to understand what you want with that statement - and that makes some sense, as it is really a strange thing to ask perl to do. ;-) "What do you mean, if this false string is true??" *grin*

Deparse on my machine also returned a real funny result:

'???';
-e syntax OK
[download]

Yes I know, Deparse is just a qualified guess. Still funny. :)

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You have moved into a dark place.
It is pitch black. You are likely to be eaten by a grue.