Struct Vi 

pub struct Vi {
    pub cursor: usize,
    pub scroll: usize,
    pub visual: Option<usize>,
    pub count: usize,
    pub g_pending: bool,
    pub pattern: String,
    pub dir: Option<Dir>,
    pub view: Cell<View>,
}

Fields

cursor: usize

selected message. only meaningful once the user has started navigating.

scroll: usize

index of the newest message on screen — the viewport anchor.

visual: Option<usize>

visual-mode anchor; the selection runs between this and the cursor.

count: usize

pending motion count (5j). 0 means none typed.

g_pending: bool

saw a bare g, waiting to see whether it’s gg / gt / gT.

pattern: String

last search pattern and direction, for n / N.

dir: Option<Dir>

view: Cell<View>

Implementations

impl Vi

pub fn reset(&mut self)

back to following live chat: no selection, pinned to the newest message.

pub fn following(&self) -> bool

are we pinned to the bottom with nothing selected? while true the cursor bar stays hidden and new messages scroll in, so live chat reads clean and the first k is what reveals the cursor (less/copy-mode behaviour).

pub fn take_count(&mut self) -> usize

consume the pending count, defaulting to 1.

pub fn push_digit(&mut self, d: u32) -> bool

accumulate a count digit. 0 only counts as a digit mid-number, matching vi (a bare 0 is a motion, and here there is no column to move to).

pub fn down(&mut self, n: usize)

move toward newer (down the file). saturates at the newest message.

pub fn up(&mut self, n: usize, last: usize)

move toward older (up the file). saturates at the oldest one loaded.

pub fn to_newest(&mut self)

G — the newest message.

pub fn to_oldest(&mut self, last: usize)

gg — the oldest message still in the ring.

pub fn selection(&self) -> Option<(usize, usize)>

the selected range as (newest_index, oldest_index), inclusive. None outside visual mode.

pub fn selected(&self, idx: usize) -> bool

is this message inside the visual selection?

pub fn keep_visible(&mut self)

pull the viewport so the cursor is on screen. count is what the last frame fit; heights vary, so this can be a row out for one frame and then settles — far cheaper than re-running layout inside the key handler.

pub fn absorb_new(&mut self, added: usize, last: usize)

new messages arrived. while the user is reading scrollback we shift the viewport and cursor by the same amount, so the pane holds still and the cursor stays on the message it was on instead of sliding underneath. once they’re back at the bottom, chat follows live again.

pub fn clamp(&mut self, last: usize)

clamp to a ring that may have shrunk (channel switched, messages evicted).

Trait Implementations

impl Default for Vi

fn default() -> Self

Returns the “default value” for a type.