[brabel]

There are a few pull requests that claim to make the code faster, but you can run the benchmarks and see none of them actually did. Why not try to improve the code I posted above and make the apparently small changes you want to make and check if it's faster or not.

I've tried a few myself and I am almost sure your hints will not work.

> some pretty bad stuff like DIGITS, using &str for something that is always a single-character ASCII digit, accessed by already having had the digit as a u8 and turning it back into a string prematurely.

The end result needs to be printing the strings so I don't see how you can work around that. Can you at least post your code doing that in a way that won't totally destroy the performance gains you may have obtained elsewhere?