It's quite common for AND to have a higher precedence than OR and for them both to be left-to-right associative. In that case. cond1 AND cond2 AND cond3 OR cond4 AND cond5 AND cond 6. would be equivalent to: ((cond1 AND cond2) AND cond3) OR ((cond4 AND cond5) AND cond 6) edited May 29, 2013 at 4:49. More @Wikipedia
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