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I don't think anyone finds recurrence relations, closed form expressions, or their derivation controversial or disagreeable in any way. On the other hand, the

I don't think anyone finds recurrence relations, closed form expressions, or their derivation controversial or disagreeable in any way. On the other hand, the implication that Lisp textbooks -- or other language texts that use fibonacci or like examples for recursion examples -- shouldn't be using simple recursive definitions as an illustration if there exists a closed form may well raise some eyebrows. What do you want, Collatz Sequences? Additionally, there's an air of attacking the sophistication of devs who choose Lisp specifically, which is the kind of thing that people frequently do find disagreeable (even if there's a reasonable case for it). Fibonacci and other linear recurrence relations are used because they're simple and often familiar intros that can help conceptualize the way recursion can reduce problems to smaller versions of themselves (which is very much mathematical thinking). They're not there because they represent limits of how Lisp devs generally do or should think.

userxyz 4y ago
> On the other hand, the implication that Lisp textbooks -- or other language texts that use fibonacci or like examples for recursion examples -- shouldn't be using simple recursive definitions as an illustration if there exists a closed form may well raise some eyebrows. I didn't imply that. I think the author laments the lack of math in LISP programming books beyond a couple of cliched examples he gave, well the "simple recursive definitions". He is not saying you shouldn't be using them, he is saying that is not adequate. That's too little. He is saying LISPers should go beyond that. My point was that you can definitely go above and beyond that into the math territory complete with coherent body of theory(a bundle of theorems and their proofs), but that will take you way off course. Especially, given that regular math textbooks contain all the relevant info. I am not even arguing the rest of what you said.

userxyz 4y ago

> On the other hand, the implication that Lisp textbooks -- or other language texts that use fibonacci or like examples for recursion examples -- shouldn't be using simple recursive definitions as an illustration if there exists a closed form may well raise some eyebrows. I didn't imply that. I think the author laments the lack of math in LISP programming books beyond a couple of cliched examples he gave, well the "simple recursive definitions". He is not saying you shouldn't be using them, he is saying that is not adequate. That's too little. He is saying LISPers should go beyond that. My point was that you can definitely go above and beyond that into the math territory complete with coherent body of theory(a bundle of theorems and their proofs), but that will take you way off course. Especially, given that regular math textbooks contain all the relevant info. I am not even arguing the rest of what you said.