I am trying to take a vec and process it's content in parallel using multiple threads.
The code I came up with is similar to this:
use std::thread;
fn main() {
let numbers = vec![1,2,3,4];
let res = numbers.chunks(2).map(|chunk| {
let joinhandler = thread::spawn(move || {
chunk.iter().map(|x| x * 2).collect::<Vec<u8>>()
});
joinhandler.join().unwrap()
}).flatten().collect::<Vec<u8>>();
println!("{:?}", res);
}
But this fail with the following error:
error[E0597]: `numbers` does not live long enough
--> src/main.rs:5:15
|
5 | let res = numbers.chunks(2).map(|chunk| {
| ^^^^^^^^^^^^^^^^^ borrowed value does not live long enough
6 |
7 | let joinhandler = thread::spawn(move || {
| ___________________________-
8 | | chunk.iter().map(|x| x * 2).collect::<Vec<u8>>()
9 | | });
| |__________- argument requires that `numbers` is borrowed for `'static`
...
14 | }
| - `numbers` dropped here while still borrowed
for the life of me, I cannot figure out how to make the borrow checker happy in this case.
PS: I know there are other approaches to processing a vec with multiple threads. This is not a question about finding other approach. This is a question about why this particular approach is not compiling and how to fix it if possible.
