gistfile1.txt

trait Visitor<T>{
	fn visit(&self, t: T);
}
struct PrintVisitor;
impl PrintVisitor {
	fn print(&self, s: ~str){
		println(s);
	}
}
impl Visitor<~str> for PrintVisitor {
	fn visit(&self, s: ~str){
		println(s);
	}
}

struct PrintReverseVisitor;
impl PrintVisitor {
	fn print(&self, s: ~str){
		println(s);
	}
}
impl Visitor<~str> for PrintReverseVisitor {
	fn visit(&self, s: ~str){
		let x: ~[char] = s.rev_iter().collect();
		println( std::str::from_chars(x));
	}
}


struct SomeObject;
impl SomeObject {
	fn do_sth<'r>(&self, v: &'r Visitor<~str>, s: ~str){
		v.visit(s);
	}
}

fn main(){
let v = &PrintVisitor;
let v1 = &PrintReverseVisitor;
let o = SomeObject;

o.do_sth(v as &Visitor<~str>, ~"Hello");
o.do_sth(v1 as &Visitor<~str>, ~"Hello");
}