One of the few lessons I distinctly remember from college was finite automata in my PL class. I really enjoyed exploring the concepts and writing a grep tool; we were supposed to write either a NFA or DFA processing application, but I decided to write both.
20 years later I got to apply some of the same ideas to a language processing application, and it was such a pleasure to actually use something conceptual like that. Made me briefly regret landing in more hybrid infrastructure/automation roles instead of pure software development.
Somewhere I may still have my copy of Preperata and Yeh that my professor recommended at the time for further reading. Like most of my books, it was never actually read, just sat around for years.
"But on a day-to-day basis, if asked to recognize balanced parentheses?"
On day-to-day basis you will never encounter this problem in pure form. As the consequence the solutions are not good for the day-to-day stuff.
Even if you only are only writting a verifier (which is already a bit unrealistic), you'll need to say something more than "not balanced". Probably rather something along the lines of "closing brace without a matching opening at [position]" or "[n] unclosed parentheses at <end of stream>" which rules out the simple recursive regex approach (counter still works).
Bummer, I thought Reginald Braithwaite was publishing again. When I first entered JavaScript world, I really enjoyed and benefited from his writing and talks.
I still enjoy writing code like the code in TFA, but these days people seem a lot less interested in code than organizing their agentic LLMs, so I don't have the same incentive to share whatI find interesting. And it would be terrible marketing, like showing up to audition for a job driving F1... In a Jaguar E-Type.
Elegant and beautiful, but that isn't the game any more.
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[ 7.5 ms ] story [ 32.8 ms ] thread20 years later I got to apply some of the same ideas to a language processing application, and it was such a pleasure to actually use something conceptual like that. Made me briefly regret landing in more hybrid infrastructure/automation roles instead of pure software development.
Somewhere I may still have my copy of Preperata and Yeh that my professor recommended at the time for further reading. Like most of my books, it was never actually read, just sat around for years.
A counter. That's the difference between theory and practice. Because in practice, everything is finite.
On day-to-day basis you will never encounter this problem in pure form. As the consequence the solutions are not good for the day-to-day stuff.
Even if you only are only writting a verifier (which is already a bit unrealistic), you'll need to say something more than "not balanced". Probably rather something along the lines of "closing brace without a matching opening at [position]" or "[n] unclosed parentheses at <end of stream>" which rules out the simple recursive regex approach (counter still works).
I still enjoy writing code like the code in TFA, but these days people seem a lot less interested in code than organizing their agentic LLMs, so I don't have the same incentive to share whatI find interesting. And it would be terrible marketing, like showing up to audition for a job driving F1... In a Jaguar E-Type.
Elegant and beautiful, but that isn't the game any more.