Use PyString::from_fmt to avoid intermediate String allocations#14248
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reaperhulk merged 1 commit intopyca:mainfrom Feb 14, 2026
Merged
Use PyString::from_fmt to avoid intermediate String allocations#14248reaperhulk merged 1 commit intopyca:mainfrom
reaperhulk merged 1 commit intopyca:mainfrom
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Replace `format!` + String with `PyString::from_fmt` + `format_args!` in __repr__ methods and one PyString::new call, writing directly to a Python string buffer (1 alloc) instead of going through format!() -> String -> PyString (2 allocs + copy). This optimization is only effective on Python 3.14+. Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
reaperhulk
approved these changes
Feb 14, 2026
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Replace
format!+ String withPyString::from_fmt+format_args!in repr methods and one PyString::new call, writing directly to a Python string buffer (1 alloc) instead of going through format!() -> String -> PyString (2 allocs + copy). This optimization is only effective on Python 3.14+.