Is there a way to iterate over items VecModel<> model, without cloning?

[qarmin]

I found, that on my OS, iterating over 800000 elements in model, took 150ms in debug mode and 30ms in release

I checked implementation and found that there is iterator

impl<T> Iterator for ModelIterator<'_, T> {
    type Item = T;

    fn next(&mut self) -> Option<Self::Item> {
        if self.row >= self.model.row_count() {
            return None;
        }
        let row = self.row;
        self.row += 1;
        self.model.row_data(row)
    }

that inside row_data implementation clones a value

    fn row_data(&self, row: usize) -> Option<Self::Data> {
        self.array.borrow().get(row).cloned()
    }

I suspect, that this cloned() may partially be responsible for slow performance.

Is there a way to iterate over model, without cloning?

[ogoffart]

Right now there isn't. The problem is the interior mutability.
Perhaps we could offer a borrow() function on VecModel that returns a core::cell::Ref<&[T]> or something like that.

The thing is that value stored into model are usually cheap to clone.