fix: correct unary minus/plus/tilde precedence#1236
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jorgsowa
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| ["+", "-", "."], | ||
| ["*", "/", "%"], | ||
| ["!"], | ||
| ["!", "u-", "u+", "u~"], // u- etc. are unary variants; higher than * so -20*5 parses as (-20)*5 |
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Not sure how relevant in practice, but according to https://www.php.net/manual/en/language.operators.precedence.php the unary operators have even higher precedence than instanceof. Would it make sense to reflect this here?
Also, tangentially, are we lacking ++ and --?
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Good point. I changed the precedence of instanceof. Pre and post increment operators, we can tackle in another branch.
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Hmm, could it be that you moved it too far? instanceof has lower precedence than the unary uperators, but higher precedence than the arithmetic operators (+, -, ., *, /, %).
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That's right. Operator ! should be split away from unary arithmetic operators.
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Unary -, +, and ~ shared the same precedence key as binary - and + (level 15), placing them below * (level 16). This caused -20 * 5 + 10 to be parsed as -(20 * 5 + 10) instead of (-20) * 5 + 10.
Add u-, u+, u~ keys to the precedence table at the ! level (17) and look them up in resolvePrecedence so unary operators correctly bind tighter than multiplicative operators.