In particular there don't seem to be crazy optimizations and non-portable stuff like you see in other production regex implementations and in interpreters. It's pure ANSI C.
The functions are all short -- no 1000 line monsters like I've seen in a lot of old C code lately.
The rsc example code is actually a great example of using pointers in C. People rightly avoid lots of raw pointers for application code, but for this use case, they yield compact and elegant code.
https://swtch.com/~rsc/regexp/
In particular there don't seem to be crazy optimizations and non-portable stuff like you see in other production regex implementations and in interpreters. It's pure ANSI C.
The functions are all short -- no 1000 line monsters like I've seen in a lot of old C code lately.
The rsc example code is actually a great example of using pointers in C. People rightly avoid lots of raw pointers for application code, but for this use case, they yield compact and elegant code.