How was it incorrect before?
According to specs, enum types _can_ be unsigned and so the test
would be always false.
Ok. I thought perhaps the first enum was set to 0, which guarantees
that all following enums are positive integers.
They are all positive integers ...
And since the enum type in this case is unsigned, an unsigned value
can never be inferior to 0 and so the test is always false.
Cheers,
Sylvain