Just started with rust!

[scottmcm]

@Arp

Another question on this, in many functional languages we prefer to write a logic recursively whenever possible rather than using a loop, what is rust's take on this? Are there any benefits to either approach?

Rust doesn't have guaranteed TCE, so it's not canonical to write things that way because they tend to stack-overflow in debug. It'll probably happen eventually as an opt-in guarantee; it comes up periodically https://github.com/rust-lang/rfcs/pull/81 https://github.com/rust-lang/rfcs/pull/1888 (Of course, LLVM will often to tail call optimization in release mode when it's profitable.)

That said, here's a post I can reuse from a while back:

When will Rust have TCO/TCE?

This won't help for general tail calls, but if you can just use tail recursion, you can use a combinator: pub fn factorial(x: usize) -> usize { tail_recurse((x, 1), |(a, b)| { if a == 0 { RecursionResult::Return(b) } else { RecursionResult::Continue((a - 1, a * b)) } }) } Amusingly, that actually generates better code than (1..=x).product()