in reply to Re^3: Boolean counter?
in thread Boolean counter?

$i appears only once, the behaviour is defined
$ perl -MO=Deparse,-p -le"print - --$i" BEGIN { $/ = "\n"; $\ = "\n"; } print((-(--$i))); -e syntax OK
You were thinking of
print(-( ++$i - --$i ))

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Re^5: Boolean counter?
by ikegami (Pope) on Dec 07, 2009 at 17:01 UTC

    While the operand evaluation order for the ops you've used in your example isn't defined, it doesn't matter (unless there's an overflow) for that example. It's just a clarity issue.

    $i appears only once, the behaviour is defined

    Except it ($Counter) appeared twice.