Simplify downcast_primitive_array!() dfn for rust-analyzer#9454
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brunal wants to merge 1 commit intoapache:mainfrom
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Simplify downcast_primitive_array!() dfn for rust-analyzer#9454brunal wants to merge 1 commit intoapache:mainfrom
brunal wants to merge 1 commit intoapache:mainfrom
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The original definition parses the whole "non-primitive" expression tree in detail. Additionally, the macro is recursive. As a consequence, calling the macro with many "non-primitive" branches and right-hand sides is expensive. In practice, this causes rust-analyzer to choke on some uses of the macro (e.g. in arrow-ord/src/cmp.rs). Increasing the recursion limit up to 10k does not solve it (and higher limits causes rust-analyzer to crash). The simple solution is to stop destructuring the "non-primitive" tree: just make it a tt*. The inner downcast_primitive_array_helper!() macro will parse it once in turn.
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Note that an intermediate improvement would be to use |
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The original definition parses the whole "non-primitive" expression tree in detail. Additionally, the macro is recursive. As a consequence, calling the macro with many "non-primitive" branches and right-hand sides is expensive.
In practice, this causes rust-analyzer to choke on some uses of the macro (e.g. in arrow-ord/src/cmp.rs). Increasing the recursion limit up to 10k does not solve it (and higher limits causes rust-analyzer to crash).
The simple solution is to stop destructuring the "non-primitive" tree: just make it a tt*. The inner downcast_primitive_array_helper!() macro will parse it once in turn.