Struct Session 

pub struct Session<'e> { /* private fields */ }

One typing session: holds the partial pinyin string the user has typed so far, exposes candidates, and commits on selection. Borrows the PinyinEngine for the dict + fuzzy config.

Implementations

impl<'e> Session<'e>

pub fn new(engine: &'e PinyinEngine) -> Self

Open a session against engine. The session holds a borrow for its lifetime; the engine itself is Send + Sync-compatible (FST is 'static, fuzzy is Copy).

pub fn input_char(&mut self, c: char)

Append one ASCII character to the input buffer. Non-ASCII or non-letter characters are silently ignored — the IME shell is responsible for filtering at the keyboard layer.

pub fn backspace(&mut self) -> bool

Drop the last input character, if any. Returns whether anything was removed.

pub fn reset(&mut self)

Clear the entire input buffer (e.g., on Esc).

pub fn input(&self) -> &str

The raw input string typed so far.

pub fn candidates(&mut self) -> &[String]

Candidates for the current input, considering fuzzy expansion. Result is borrowed from the session’s reused buffer; subsequent calls invalidate the previous slice.

Empty input yields an empty slice.

pub fn lookup_into(&self, out: &mut Vec<String>)

Same as Self::candidates but writes into a caller-owned buffer. Useful for FFI callers that own the buffer’s lifetime independently of the session.

pub fn commit(&mut self, idx: usize) -> Option<String>

Commit the candidate at index idx, returning the committed word and resetting the input buffer. Out-of-range indices yield None and leave the session untouched.

Side effect: records the pick in the engine’s L0 layer (item 28). Three consecutive picks of the same (input, word) auto-pin it to position 0 for that input. Pinyin v0.2 ignores the fuzzy expansion for L0 attribution — record uses the literal user input string, matching what dict.exists_in_l1 will accept.