hi,
I am a new beginner in Rust. I have a list of structs in a vector, which I am trying to iterate, filter and update matching values.
From docs, my understanding is that when we iterate and filter a vector, the result is a new/copy of the vector, not the original one.
How to approach this, the option I see while searching online is to use afor loop with an index.
for i in 0...vec.len(){}
code i am trying to do
ex :

pub struct Item {
    pub name: String,
    pub sell_in: i32,
    pub quality: i32,
}
    let items = vec![
        Item::new("+5 Dexterity Vest", 10, 20),
        Item::new("Aged Brie", 2, 0),
        Item::new("Elixir of the Mongoose", 5, 7),
        Item::new("Sulfuras, Hand of Ragnaros", 0, 80),
        Item::new("Sulfuras, Hand of Ragnaros", -1, 80),
        Item::new("Backstage passes to a TAFKAL80ETC concert", 15, 20),
        Item::new("Backstage passes to a TAFKAL80ETC concert", 10, 49),
        Item::new("Backstage passes to a TAFKAL80ETC concert", 5, 49),
        Item::new("Conjured Mana Cake", 3, 6),
    ];
    pub fn update_quality(&mut self) {
        let back_stage_iter: Vec<&Item> = self
            .items
            .iter()
            .filter(|&x| {
                x.name == "Backstage passes to a TAFKAL80ETC concert"
                    && x.sell_in < 11
                    && x.quality < 50
            })
            .collect();

        for v in back_stage_iter {
            *v.quality = *v.quality + 1;
        }

In the above *v.quality=*v.quality+1 am getting me can not assign a value to a reference.

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