https://www.spinellis.gr/blog/20060626/cpp.algo.pdf https://www.spinellis.gr/blog/20060626/cpp.algo.pdf was actually very useful. With that doc, I could impleme

https://www.spinellis.gr/blog/20060626/cpp.algo.pdf https://www.spinellis.gr/blog/20060626/cpp.algo.pdf was actually very useful. With that doc, I could implement a preprocessor without thinking too much about how it should work in details. In that sense, even after I implemented a C preprocessor, I don't feel I fully understand how it works.