perf: reduce llvm-lines in attr.rs: DisplayPath::fmt #1945
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dtolnay
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Nov 20, 2025
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Most of that reduction is coming from write!(formatter, "{}", expr)➡️Display::fmt(&expr, formatter).
That transformation is not generally correct inside a Display impl. When there is width, fill, alignment, or other formatting options on the incoming formatter, applying those onto every path segment is almost certainly not what the caller would expect.
I am open to arranging this code in some way that is not a Display impl, but while it is a Display impl it needs to be written correctly as a Display impl.
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186 llvm-lines less on
rustc 1.91.1