Rust

/// make a ref-circle, it's possible in rust. /// but rust make sure it safe. use std::rc::Rc; use std::cell::RefCell; use crate::List::{Cons, Nil}; #[derive(Debug)] enum List{ Cons(i32, RefCell<Rc<List>>), Nil } impl List { fn tail(&self) -> Option<&RefCell<Rc<List>>> { match self { Cons(_, item) => Some(item), Nil => None, } } } fn main() { let a = Rc::new(Cons(5, RefCell::new(Rc::new(Nil)))); println!("a initial rc count = {}", Rc::strong_count(&a)); println!("a next item = {:?}", a.tail()); let b = Rc::new(Cons(10, RefCell::new(Rc::clone(&a)))); println!

concurrent-programming: programs can run in independent with each other. parallel programming: program can run at same time. as a low-level language, rust need less abstraction and more control. use thread process vs thread programs: Race conditions: data-race. resource-race. DeakLock difficult concurrent bug. os-thread vs green-thread: 1:1 vs M:N /// thread examples /// when the main-thread exit, the fork-thread will exit too. /// just like python thread.deamon flag. use std::thread; use std::time::Duration; fn main() { thread::spawn(|| { for i in 1.

concurrent-programming: programs can run in independent with each other. parallel programming: program can run at same time. as a low-level language, rust need less abstraction and more control. use thread process vs thread programs: Race conditions: data-race. resource-race. DeakLock difficult concurrent bug. os-thread vs green-thread: 1:1 vs M:N /// thread examples /// when the main-thread exit, the fork-thread will exit too. /// just like python thread.deamon flag. use std::thread; use std::time::Duration; fn main() { thread::spawn(|| { for i in 1.