alt Hacker NewsThis is very interesting. I'm a bit skeptical about the benchmarks / performance claims because they seem almost too good to be true but even just the extended operators alone are a nice improvement over existing regex engines.
The post mentions they also have a native library implemented in Rust without dependencies but I couldn't find a link to it. Is that available somewhere? I would love to try it out in some of my projects but I don't use .NET so the NuGET package is of no use to me.
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I second this request. It would be wonderful to be able to test the rust implementation since it easier to call from other languages in my typical setup. I have a couple uses cases I have never fully resolved, just implemented partial work arounds and accepted a restricted feature set. This would probably allow me to deal with them correctly.
There's currently only a string solver with the same core library, but not a full regex engine https://github.com/ieviev/cav25-resharp-smt
I will open source the rust engine soon as well, some time this month.
As for the benchmarks, it's the fastest for large patterns and lookarounds, where leftmost-longest lets you get away with less memory usage so we don't need to transition from DFA to NFA.
In the github readme benchmarks it's faster than the exponential implementations of .NET Compiled so the 35 000x can be an arbitrary multiplier, you can keep adding alternatives and make it 1000000x.
for a small set of string literals it will definitely lose to Hyperscan and Rust regex since they have a high effort left-to-right SIMD algorithm that we cannot easily use.