Struct ChangeBank 

pub struct ChangeBank {
    pub last_edit: Option<(usize, usize)>,
    pub list: Vec<(usize, usize)>,
    pub cursor: Option<usize>,
    pub u_line: Option<(usize, String)>,
    pub last_edit_end: Option<(usize, usize)>,
}

Per-buffer changelist bank: g;/g, history plus the '. / `. “last change” mark. Shared via Arc<Mutex<ChangeBank>> across every window’s Editor viewing the SAME buffer — vim’s changelist and last-change mark are per-buffer, not per-window, so an edit made in one split must be visible to g; / `. from any other split on that buffer (audit B3).

UNLIKE GlobalMarks / [Registers] / SearchBank / abbrevs / last-substitute — which are each a single Arc shared by literally every Editor in the app, session-global — a ChangeBank is per-buffer: the app layer keys a bank per buffer_id and hands each Editor the Arc for its CURRENT buffer, swapping it whenever the editor’s buffer changes (see App::change_bank_for / Editor::set_change_bank_arc). Two editors on the same buffer_id share one bank; editors on different buffers never see each other’s entries.

Fields

last_edit: Option<(usize, usize)>

Position of the most recent buffer mutation, matching vim’s :h '. (“the position where the last change was made” — change-start, not the post-edit cursor). Surfaced via the '. / `. marks.

list: Vec<(usize, usize)>

Bounded ring of recent edit positions (newest at back). g; walks toward older, g, toward newer. Capped at crate::types::CHANGE_LIST_MAX.

cursor: Option<usize>

Index into list while walking; None outside a walk (any new edit clears it and trims forward entries).

u_line: Option<(usize, String)>

U (:h U) bookkeeping: (row, text) — the text of row before the first change landed on it since the tracked row last changed. Reset (row + fresh snapshot) whenever an edit’s pre-edit cursor row differs from the currently tracked row. Editor::undo_line swaps this to the pre-U text on each call so a second U redoes what the first one undid.

last_edit_end: Option<(usize, usize)>

Post-edit cursor position of the most recent mutate_edit call — NOT part of any undo/redo snapshot (deliberately: after an undo/ redo this goes stale and the next edit correctly starts a fresh burst). Lets mutate_edit tell whether the next edit is a continuation of the same typing burst (its pre-edit position picks up exactly where this one left the cursor) or the start of a new one — see the entry comment in mutate_edit for why this matters for g; / `.: a whole AXYZ<Esc> insert session is ONE vim change, not three, and g; from a fresh cursor lands on its start column, not the last-typed character’s.

Trait Implementations

impl Clone for ChangeBank

fn clone(&self) -> ChangeBank

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ChangeBank

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for ChangeBank

fn default() -> ChangeBank

Returns the “default value” for a type.