逗

gistfile1.rs

#![feature(box_syntax)]
use std::ops::DerefMut;
use std::ops::Deref;
 
#[derive(Show)]
struct List<T> {
	car: T,
	cdr: Option<Box<List<T>>>,
}


fn remove<T: Eq+Clone>(node: Box<List<T>>, pv: T, value: T) -> List<T> {
	let mut now = node;
	let tmp = now.car.clone();
	if tmp == value {
		return List { car: pv, cdr: now.cdr };
	} else {
		match now.cdr {
			None => (),
			Some(n) => now = box remove(n, tmp, value),
		};
		return List { car: pv, cdr: Some(now) };
	}
}


fn main() {
	let mut head = Box::new(List {car: 0i8, cdr: None});
	for i in range(1, 42i8) {
		head = Box::new(List {car: i, cdr: Some(head)})
	}
	let tmp = head.car.clone();
	head = box remove(head, tmp, 5);
	println!("{:?}", head);
}