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0 pointssimoncion4mo ago0 comments

To put it another way: anything you can express with iteration, you can express with recursion (just as long as you don't run out of call stack).

Once you get it, it's obvious, but if you're not already familiar with the notion, the understanding can be pretty amazing.

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sodapopcan4mo ago

> just as long as you don't run out of call stack

And with tail-call you don't even need to worry about that :)

simoncionOP4mo ago

Of course, that assumes that you write your functions so that they can be converted into iteration!

Did you know that some C/C++ compilers will do tail-call -er- optimization? I learned this quite a while ago, so I'd expect every major C/C++ compiler to do it by now, but I was pretty impressed at the time.

sodapopcan4mo ago

> Of course, that assumes that you write your functions so that they can be converted into iteration!

I was indeed assuming this, however due to my lack of compiler knowledge, not explicitly writing your functions--at least in the classic way--doesn't necessarily mean you Erlang functions won't be optimized. See section 2.3 [0]

Though again, I don't know shit about compilers and while I can imagine what callER optimized calls could look like, I would need some examples!

[0] https://www.erlang.org/docs/19/efficiency_guide/myths

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0 pointssimoncion4mo ago0 comments

To put it another way: anything you can express with iteration, you can express with recursion (just as long as you don't run out of call stack).

Once you get it, it's obvious, but if you're not already familiar with the notion, the understanding can be pretty amazing.

0 comments

sodapopcan4mo ago

> just as long as you don't run out of call stack

And with tail-call you don't even need to worry about that :)

simoncionOP4mo ago

Of course, that assumes that you write your functions so that they can be converted into iteration!

sodapopcan4mo ago

> Of course, that assumes that you write your functions so that they can be converted into iteration!

Though again, I don't know shit about compilers and while I can imagine what callER optimized calls could look like, I would need some examples!

[0] https://www.erlang.org/docs/19/efficiency_guide/myths

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