fn main() {
const s: &str = "⊗ symbol";
const n: usize = s.chars().count();
let mut a: [char; n];
}
Have you copied the code to a text file and pointed rustc
at it?
For example, say the code is in main.rs
...
$ rustc main.rs
At this time, I'd suggest just using a Vec<char>
rather than stack-allocating a fixed sized array. Something like
fn main() {
const s: &str = "⊗ symbol"
let n = s.chars().count();
let mut a = vec![char; n];
}
If you really need n
as a const, there are ways of doing that, but it'll be significantly more complicated than just using a vec, and in 99% of cases I would say it's not worth it.
It will be possible to easily count a string's characters in future versions of rust, but const
evaluation is not a complete feature today, and cannot do all general computation.
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