[Merged by Bors] - fix(init/core): lower precedence of unary -
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This commit moves the precedence of unary `-` below that of `^` so that `-a^n` parses as `-(a^n)` and not (as formerly) `(-a)^n`. It would be reasonable to move `-` below `*` as well (so that `-a*b` parses as `-(a*b)`) but this is surprisingly disruptive to mathlib, because `∩` and `⊓` have the same precedence as `*` and `-` is also used for set complement. So, at least for now, we leave the relative precedence of `-` and `*` unchanged.
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This commit moves the precedence of unary `-` below that of `^` so that `-a^n` parses as `-(a^n)` and not (as formerly) `(-a)^n`. It would be reasonable to move `-` below `*` as well (so that `-a*b` parses as `-(a*b)`) but this is surprisingly disruptive to mathlib, because `∩` and `⊓` have the same precedence as `*` and `-` is also used for set complement. So, at least for now, we leave the relative precedence of `-` and `*` unchanged.
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This commit moves the precedence of unary
-below that of^so that
-a^nparses as-(a^n)and not (as formerly)(-a)^n.It would be reasonable to move
-below*as well (so that-a*bparses as-(a*b)) but this is surprisingly disruptiveto mathlib, because
∩and⊓have the same precedence as*and
-is also used for set complement. So, at least for now,we leave the relative precedence of
-and*unchanged.