Raúl Marín b2e41e8b88 Keep chars_format::javascript out of the common hot path ... 8.3.0 added the ECMAScript leading-zero rule as a runtime test on fmt inside parse_number_string, so unlike basic_json_fmt its error returns and Annex B octal scan land in the parser body that every from_chars instantiation force-inlines. from_chars_caller<double>::call grew from 935 to 1031 instructions and other formats lost about 3% on short inputs. Make the rule a compile-time parameter of the parser body, selected once at the entry point, and take chars_format::javascript out to a cold conversion before anything else is live so the branch is a tail call. parse_number_string keeps its signature and behaviour. benchmarks/benchmark.cpp, Intel Xeon 6975P-C, clang 22.1.8, cycles per float, best of 7: canada.txt mesh.txt 8.2.10 47.03 24.78 8.3.0 47.34 26.08 this 46.28 24.86		2026-09-21 19:47:21 +00:00
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fast_float	Keep chars_format::javascript out of the common hot path	2026-09-21 19:47:21 +00:00