Struct reedline::FileBackedHistory

pub struct FileBackedHistory { /* private fields */ }

Stateful history that allows up/down-arrow browsing with an internal cursor.

Can optionally be associated with a newline separated history file using the FileBackedHistory::with_file() constructor. Similar to bash’s behavior without HISTTIMEFORMAT. (See https://www.gnu.org/software/bash/manual/html_node/Bash-History-Facilities.html) If the history is associated to a file all new changes within a given history capacity will be written to disk when History is dropped.

Implementations

impl FileBackedHistory

pub fn new(capacity: usize) -> Result<Self>

Creates a new in-memory history that remembers n <= capacity elements

pub fn with_file(capacity: usize, file: PathBuf) -> Result<Self>

Creates a new history with an associated history file.

History file format: commands separated by new lines. If file exists file will be read otherwise empty file will be created.

Side effects: creates all nested directories to the file

Trait Implementations

impl Debug for FileBackedHistory

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

Formats the value using the given formatter.

impl Default for FileBackedHistory

fn default() -> Self

Creates an in-memory History with a maximal capacity of HISTORY_SIZE.

To create a History that is synchronized with a file use FileBackedHistory::with_file()

Panics

If HISTORY_SIZE == usize::MAX

impl Drop for FileBackedHistory

fn drop(&mut self)

On drop the content of the History will be written to the file if specified via FileBackedHistory::with_file().

impl History for FileBackedHistory

fn save(&mut self, h: HistoryItem) -> Result<HistoryItem>

only saves a value if it’s different than the last value

fn sync(&mut self) -> Result<()>

Writes unwritten history contents to disk.

If file would exceed capacity truncates the oldest entries.

fn load(&self, id: HistoryItemId) -> Result<HistoryItem>

load a history item by its id

fn count(&self, query: SearchQuery) -> Result<i64>

retrieves the next unused session id count the results of a query

fn search(&self, query: SearchQuery) -> Result<Vec<HistoryItem>>

return the results of a query

fn update( &mut self, _id: HistoryItemId, _updater: &dyn Fn(HistoryItem) -> HistoryItem ) -> Result<()>

update an item atomically

fn clear(&mut self) -> Result<()>

delete all history items

fn delete(&mut self, _h: HistoryItemId) -> Result<()>

remove an item from this history

fn session(&self) -> Option<HistorySessionId>

get the history session id

fn count_all(&self) -> Result<i64>

return the total number of history items