Austin I'm running into some not-fun parts now. Constructing the NFA isn't hard, but after that I'm between a rock and a hard spot. Running the equivalent DFA on the (potentially very large) input string is fast, but if the NFA has n states, the DFA could have up to 2ⁿ. Oof. Or you could run the NFA directly, but it could be in all n states for each character in the input string. n*m vs 2ⁿ, ouch
What's wrong with regex? The trick is to break it down into components that you can read without a brain double panic. A little string catenation at run time won't hurt, I promise
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Yeah, converting that to OG line numbered BASIC isn't happening anytime soon 😂
Edit: Actually, those regexps match up pretty closely to how I'd approach the problem in old BASIC, even if I didn't have anything like InStr or IndexOf and could examine a string only one character at a time in a For loop. It might look a bit like a state machine or DFA