this post was submitted on 04 Mar 2024
944 points (97.4% liked)
Programmer Humor
32611 readers
50 users here now
Post funny things about programming here! (Or just rant about your favourite programming language.)
Rules:
- Posts must be relevant to programming, programmers, or computer science.
- No NSFW content.
- Jokes must be in good taste. No hate speech, bigotry, etc.
founded 5 years ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
Not an OCaml expert either but that looks tail recursive, you're never going to blow the stack.
You can tell by how after the recursive call within aux, its result does not get used within the function. That means that the compiler doesn't need to push a return address to the stack as the only code that would be at that address is instructions to pop another address and return there, we can short-circuit all that and jump from the base case (0) directly to where aux(10000) is supposed to return to instead of taking 10000 dumb steps (like practically all procedural languages do because they don't have tail call optimisation).
This would've been different if you had concatenated the string not as an argument to aux.
I thought Tail recursion just gets turned into an iterative loop by the compiler? Hence why you won’t get a stack overflow. And since in procedural languages you can just use a loop in place of a tail recursive function you would never run into this problem, right? At least this is how it was taught to me when I was learning about it in lisp.
Yes you still need the loop part I skipped over that one, only focussing on the "why no return address on the stack" part. It's what you need to focus on to see whether a recursive call is in a tail position and if it is the compiler does the rest no need to worry about that part.
That was the idea. But I'm not a functional programmer (not a programmer by profession at all lol), so I might've done something stupid. Hence the disclaimer. Thanks for confirming.
OCaml certainly isn't a bad language to learn for a non-professional. It's almost painfully sensible and well-engineered, you're far away from hype train nonsense and startup production jank but also not out in the "the purpose of this language is to be beautiful and earn me a PhD" territory, OCaml definitely is a production language.