In the case of !!1 it seems to only be just a performance thing

I think so. It is slightly different — I can get pPOK+pIOK+pNOK, but I can't also get IOK+NOK+POK — so there could be difference, but I don't know of any.

In reply to Re^6: Why is Dumper returning "!!1" for true file test? by ikegami
in thread Why is Dumper returning "!!1" for true file test? by nysus

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