Class Foo

toys/inter/src/main.rs:3–10

use std::sync;

struct Foo {
    mu1: sync::Arc<sync::Mutex<i32>>,
    rw1: sync::RwLock<i32>,
    mu2: parking_lot::Mutex<i32>,
    rw2: parking_lot::RwLock<i32>,
    mu3: spin::Mutex<i32>,
    rw3: spin::RwLock<i32>,
}

impl Foo {
    fn new() -> Self {