On 2019-Sep-24, Kyotaro Horiguchi wrote:
> Sorry, it's not a boolean. A tristate value. From the definition
> (Back, NoMove, Forward) = (-1, 0, 1), (dir1 == -dir2) if
> NoMovement did not exist. If it is not guranteed,
>
> (dir1 != 0 && dir1 == -dir2) ?
Maybe just add ScanDirectionIsOpposite(dir1, dir2) with that
definition? :-)
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Álvaro Herrera https://www.2ndQuadrant.com/
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