Re^4: How am i doing?

ChatGPT agrees, HOW CAN I BE WRONG? ;-P

Yes I'm sure, because I've seen it multiple times used this way, IIRC also in HOP.

The F(n) = F(n-1) + F(n-2) for n > 1 part is straightforwardly implemented with recursion.

> implementing the Fibonacci sequence by recursion is very ineffective.

(Slightly nitpicking) It's inefficient but effective!

The point is you get a correct result, even if you waste processing power.

The "memoisation" you mentioned solves this efficiency problem of needlessly recalculating known results.

IOW, the schoolbook continues evolving the example to deeper depth (sic).

Keep in mind that the classic MIT lectures on programming used to be in Lisp and original Lisp didn't have loops, only those "tail recursions".

Cheers Rolf
_{(addicted to the Perl Programming Language :)

see Wikisyntax for the Monastery}

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Re^5: How am i doing? by hippo (Archbishop) on Jul 21, 2025 at 10:38 UTC
Yes, you do recall correctly. From section 1.8 of HOP (page 33 in my version): Sometimes a problem appears to be naturally recursive, and then the recursive solution is grossly inefﬁcient. A very simple example arises when you want to compute Fibonacci numbers. This is a rather unrealistic example, but it has the beneﬁt of being very simple. 🦛	[reply]
Re^6: How am i doing? by choroba (Cardinal) on Jul 21, 2025 at 11:44 UTC
> Keep in mind that the classic MIT lectures on programming used to be in Lisp and original Lisp didn't have loops, only those "tail recursions". I know pretty well, and that's not just Lisp. At $job-2, we had a significant codebase in Erlang, which doesn't have loops, either. `map{substr$_->[0],$_->[1]\|\|0,1}[\\|\|{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^ARGV,3]`	[reply] [d/l]
Re^7: How am i doing? by LanX (Saint) on Jul 21, 2025 at 12:20 UTC
IIRC Fibonacci was also heavily used to show the advantages of Haskell in one of the canonical books. But unfortunately I never went thru learning Haskell. Cheers Rolf _{(addicted to the Perl Programming Language :) see Wikisyntax for the Monastery}	[reply]
Re^8: How am i doing? by Fletch (Bishop) on Jul 21, 2025 at 13:26 UTC
Re^8: How am i doing? by jaredor (Priest) on Jul 29, 2025 at 19:00 UTC