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Comment by blux | Hacker News Reader

Did you verify their claims or are you just calling BS and that's it? The new functions are in fact much faster than their C equivalent (and yes, I did verify that).

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Care to explain and show the details?

"Extraordinary claims require extraordinary It also don't do locale based things.

How not?

It compiles from sources, can be better in-lined, benefits from dead code elimination when you don't use unusual radix. iv>

Your original claim "I've not checked but this guy, and by extension the C++ standards committee who worked on this new API, are probably full of shit" was pretty extraordinary.

Look at the compiler-generated instructions yourself if you don't believe the source that I linked; in the cases I've seen all the extra new stuff just adds another layer on top of existing functions and if the former are faster the latter must necessarily also be.

The standards committee's purpose is to justify their own existence by coming up with new stuff all the time. Of course they're going to try to spin it as better in some way.

I wrote this library once; https://github.com/ton/fast_int.

Removed `std::atoi` from the benchmarks since it was performing so poorly; not a contender. Should be easy to verify.

Rough results (last column is #iterations):

  BM_fast_int<std::int64_t>/10                  1961 ns         1958 ns       355081 2973 ns         2969 ns       233953 3636 ns         3631 ns       186585 4314 ns         4309 ns       161831 5184 ns         5179 ns       136308 5867 ns         5859 ns       119398 2235 ns         2232 ns       316949 3446 ns         3441 ns       206437 3561 ns         3556 ns       197795 3650 ns         3646 ns       188613 4248 ns         4243 ns       165313 4979 ns         4973 ns       140722 10248 ns        10234 ns        69021 10996 ns        10985 ns        63810 12238 ns        12225 ns        56556 13606 ns        13589 ns        51645 14984 ns        14964 ns        47046 16226 ns        16206 ns        43279 2162 ns         2160 ns       302880 2410 ns         2407 ns       282778 3309 ns         3306 ns       208070 5034 ns         5028 ns       100000 6282 ns         6275 ns       107023 7267 ns         7259 ns        96114 2670 ns         2666 ns       262721 3547 ns         3542 ns       196704 4643 ns         4638 ns       154391 5056 ns         5050 ns       132722 6207 ns         6200 ns       111565 7113 ns         7105 ns        98847

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