You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: list.rs
    path of file: ./repos/zed/crates/gpui/src/elements
    
    the code of the file until where you have to start completion: //! A list element that can be used to render a large number of differently sized elements
//! efficiently. Clients of this API need to ensure that elements outside of the scrolled
//! area do not change their height for this element to function correctly. In order to minimize
//! re-renders, this element's state is stored intrusively on your own views, so that your code
//! can coordinate
    
    fn logical_scroll_top(&self) -> ListOffset {
        self.logical_scroll_top
            .unwrap_or_else(|| match self.alignment {
                ListAlignment::Top => ListOffset {
                    item_ix: 0,
                    offset_in_item: px(0.),
                },
                ListAlignment::Bottom => ListOffset {
                    item_ix: self.items.summary().count,
                    offset_in_item: px(0.),
                },
            })
    }