Multithreading – when using a method in a thread, “the type does not meet the required lifecycle”

I tried to use a method in a thread in rust, but I received the following error message

Here is the sample code:

use std::thread;
use std::sync::mpsc;

struct MyStruct {
    field: i32
}

impl MyStruct {
    fn my_fn(&self,adder1: i32,adder2: i32) -> i32 {
        self.field + adder1 + adder2
    }

    fn threade_test(&self) {
        let (tx,rx) = mpsc::channel();
        let adder = 1;
        let lst_adder = vec!(2,2,2);

        for a in lst_adder {
            let tx = tx.clone();

            thread::spawn(move || {
                let _ = tx.send(self.my_fn(adder,a));
            });
        }

        println!("{}",rx.recv().unwrap());
    }
}

fn main() {
    let ms = MyStruct{field: 42};
    ms.threade_test();
}

Test it on the Rust Playground.

Solution

The problem is that each variable moved to a thread must have a lifetime 'static That is, a thread cannot reference a value that does not belong to the thread

In this case, the problem is that self is a reference to the mystruct instance

To fix this problem, delete each reference and clone the structure before sending it to the thread

use std::thread;
use std::sync::mpsc;

#[derive(Clone)]
struct MyStruct {
    field: i32
}

impl MyStruct {
    fn my_fn(&self,2);

        for a in lst_adder {
            let tx = tx.clone();

            let self_clone = self.clone();
            thread::spawn(move || {
                let _ = tx.send(self_clone.my_fn(adder,rx.recv().unwrap());
    }
}

fn main() {
    let ms = MyStruct{field: 42};
    ms.threade_test();
}