Re:Is there a regular expression to detect a valid regular e...
by mannykannot on Sunday September 08, 2019 @11:11AM
(#20910997)
There is an importance to theoretical considerations that goes beyond their immediate practical applications. Ultimately, it comes down to how well one understands what is going on.
Having said that, I think there are practical applications. Suppose you were unaware of this result, and thought a true RE could validate your input? A more knowledgeable attacker might be able to craft an input that exploits the inherent limitations of your validator.
Also in practice, attempting to write a true RE to parse a language that allows restricted recursion rapidly becomes complicated. It is the wrong tool for the job.
Having said that, I think there are practical applications. Suppose you were unaware of this result, and thought a true RE could validate your input? A more knowledgeable attacker might be able to craft an input that exploits the inherent limitations of your validator.
Also in practice, attempting to write a true RE to parse a language that allows restricted recursion rapidly becomes complicated. It is the wrong tool for the job.