c0nstantine

8 ms·

1. 31.▲
   by c0nstantine 2y ago

   Typo. Fixed. Thanks. Too many cats in examples.
2. 32.▲
   Show HN: Transductive regular expressions for text editing(github.com)

   263 points by c0nstantine 2y ago|102 comments
3. 33.▲
   by c0nstantine 4y ago

   Hi, thanks for sharing. Didn't know there is a python implementation. Your article is broader and I like the functional flavor. For the 'compaction' you mention, yes it is useful. But the code will be more complicated and opt
4. 34.▲
   by c0nstantine 4y ago

   I think I got your point. It is valid. To construct the DFA and have a finite number of derivatives we have to keep track of the following equivalences: r + r ~ r r + s ~ s + r (r + s) + t ~ r + (s + t) In [1] authors state this and refer t
5. 35.▲
   by c0nstantine 4y ago

   Thanks for sharing. I am not familiar with Agda. Will take a look. There is somewhat similar code in COQ: https://github.com/coq-community/regexp-Brzozowski
6. 36.▲
   by c0nstantine 4y ago

   I agree. There is no magic. DFA construction has a risk of exponential growth in the number of states. My point was to illustrate the technique. I found no minimalistic python implementations and decided to write one with a short and gentle
7. 37.▲
   by c0nstantine 4y ago

   I don't think Rust regex engine relies on this technique. I guess the main point is when you construct the DFA directly you still have the possibility of the exponential explosion of the number of states. That's why modern engines
8. 38.▲
   by c0nstantine 4y ago

   Yes there's a typo. Thank you for following the README.md and your attention. It's fixed now.
9. 39.▲
   Show HN: Regex Derivatives (Brzozowski Derivatives)(github.com)

   103 points by c0nstantine 4y ago|35 comments