`LazyLock` mutable global vars, supported?

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1

Does LazyLock support mutable global variables?

2

The LazyLock type is for global variables that are lazily initialized on first access. After that, the value will be immutable.

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You use interior mutability (atomic types, Mutex, RwLock) with LazyLock:

use std::sync::{LazyLock, Mutex};

static FOO: LazyLock<Mutex<String>> = LazyLock::new(Default::default);

fn main() {
    dbg!(&*FOO.lock().unwrap());
    *FOO.lock().unwrap() = "Hello".to_string();
    dbg!(&*FOO.lock().unwrap());
}
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