/**
 * LocalAgreement for rolling re-transcription.
 *
 * Each interim pass re-transcribes the whole utterance so far. Words two
 * consecutive passes agree on are committed; the rest is the tail, which the
 * next pass may still change. The committed prefix never shrinks: once a
 * caption has been shown as stable it must not flicker back, even when a
 * later pass hears the start differently (the next final pass is the place
 * where the whole utterance is settled).
 *
 * @module voice/streaming/localAgreement
 */
import type { STTLocalAgreementState, STTLocalAgreementUpdate } from "../../types/index.js";
/** Splits a transcript into words on any whitespace. */
export declare function splitWords(text: string): string[];
/** Length of the shared prefix of two word lists. */
export declare function commonPrefixLength(a: string[], b: string[]): number;
export declare function createLocalAgreement(): STTLocalAgreementState;
/**
 * Folds one pass into the state and returns the split for display. Words
 * this pass agrees on with the previous one, beyond what is already
 * committed, are appended to the committed list; the words already committed
 * are kept as they were shown — they are never re-read from the new pass, so
 * a later pass that hears the start differently (or comes back shorter)
 * cannot shrink or rewrite them. The tail is whatever this pass has past the
 * committed count.
 */
export declare function updateLocalAgreement(state: STTLocalAgreementState, text: string): STTLocalAgreementUpdate;
/** Forgets everything, e.g. when another engine takes the utterance over. */
export declare function resetLocalAgreement(state: STTLocalAgreementState): void;