Shared via Rust Playground

playground.rs

#[derive(Debug)]
struct S {
    v: Vec<i32>,
}

impl S {
    fn objects_at(&self, pos: i32) -> ObjectsIter {
        ObjectsIter { it: self.v.iter(), pos: pos }
    }
}

struct ObjectsIter<'a> {
    it: std::slice::Iter<'a, i32>,
    pos: i32,
}

impl<'a> Iterator for ObjectsIter<'a> {
    type Item = i32;
    
    fn next (&mut self) -> Option<Self::Item> {
        while let Some(p) = self.it.next() {
            if self.pos == *p {
                return Some(*p);
            }
        }
        
        None
    }
}

fn main() {
    let s = S { v: vec![1, 2, 3, 2] };
    println!("{:?}", s);
    
    for v in s.objects_at(2) {
        println!("{}", v);
    }
    
    println!("{:?}", s);
}