Function with_iter_stack 

pub fn with_iter_stack<T, I: IntoIterator<Item = T>, F: FnOnce(Substack<'_, T>) -> U, U>(
    iter: I,
    callback: F,
) -> U

Recursively walk an iterator, building a Substack from its items.

Aborts

If the iterator is long, this will overflow the stack. Be very careful with calling it on iterators of unknown length, or in an already recursive context.