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by m_rcin 2672 days ago
The big difference between RapidJson and sajson is surprising to me. When I benchmarked them their performance was comparable: https://github.com/project-gemmi/benchmarking-json . Did you use RapidJson in full-precision mode?

By the way, nativejson-benchmark (from RapidJson) has a nice conformance checker that tries various corner cases. But you probably know it.
1 comments
glangdale 2672 days ago
More performance details beyond what's on the site will follow (in a while).

We use RapidJSON in the high-performance mode not the funky mode that minimizes FP error (which is some astounding work - I had no idea that strtof was so involved!). Number conversion is not our #1 focus - doing it well is nice, but all implementations have access to the same FP tricks, so you don't really learn much by going wild on this aspect.

At least, you don't unless FP conversion is your focus, in which case you should share your FP conversion code with everyone!

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leeter 2671 days ago
You should take a look at std::from_chars IIRC it can completely destroy other parsers within the stdlib because it's not intended to take locale into consideration.

https://en.cppreference.com/w/cpp/utility/from_chars

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