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So. Rust. I need an array of strings. The array must be dynamically growable at runtime. The strings are not known until runtime, but once known are immutable. If they are removed from the vector they should be freed. I said: static mut root:Vec<str> = Vec(); It did NOT like it

mcc

@mcclure111

Feb 26, 2021

Am I - On the right track, I just initialized that empty vector wrong - On the wrong track, str is compile time only, I should use String for this - Technically on the right track, I could do this with str, but I should just do it with String because it's totes efficient enough

Brendan Zabarauskas

@brendanzab

Feb 26, 2021

`Vec<String>` is what you want. `String` is a dynamically allocated string on the heap - kind of like `StringBuilder` in Java. `str` is unicode data of unknown size - but you usually see it behind a reference: `&str`. On it's own it's not usually super useful for most people.

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and

Another way of looking at it is that `String` is UTF-8 encoded `Vec<u8>` under the hood, and `str` is `[u8]` under the hood. `String`/`str` are really bad names - they were more the result of an awkward compromise back when the `~` sigil was being removed. 😅

5:50 AM · Feb 26, 2021Twitter Web App

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Okay. I 80% understand that and I think it will be very useful once I've got the other 20%

Brendan Zabarauskas

@brendanzab

Feb 26, 2021

I highly recommend checking out the docs, they are pretty good! Probably better than my explanations: - doc.rust-lang.org/std/string/str - doc.rust-lang.org/std/primitive.

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