/**
 * A GADDAG (Gordon, 1994) stored as flat typed arrays for speed and compact serialization.
 *
 * For every word `w` and every split `1 <= s <= |w|` the automaton accepts
 * `reverse(w[0..s)) + ◇ + w[s..)` (the separator is omitted when `s === |w|`).
 *
 * States are identified by "refs": `ref = (firstArcIndex << 1) | isWordEnd`.
 * A `firstArcIndex` of 0 means the state has no outgoing arcs; ref 0 means "no such state".
 * Arcs of a state are contiguous; the last one is marked with {@link LAST_ARC_FLAG} in its label.
 * An arc label stores the letter index (1..63, 0 = separator) in its low 6 bits.
 */
export declare class Gaddag {
    /** Arc labels: letter index | LAST_ARC_FLAG. Index 0 is an unused sentinel. */
    readonly arcLabels: Uint8Array;
    /** Arc targets: encoded state refs. Index 0 is an unused sentinel. */
    readonly arcTargets: Int32Array;
    /** Ref of the root state. */
    readonly rootRef: number;
    /** Code point of each letter index (position 0 holds the code point of letter 1). */
    readonly charCodes: Int32Array;
    private readonly letterByCharCode;
    constructor(arcLabels: Uint8Array, arcTargets: Int32Array, rootRef: number, charCodes: Int32Array);
    static deserialize(bytes: Uint8Array): Gaddag;
    serialize(): Uint8Array;
    /** Number of arcs (including the unused sentinel at index 0). */
    get arcsCount(): number;
    /**
     * Follows the arc labeled with `letter` from the state `ref` points at.
     * Returns the target ref, or 0 when there is no such arc.
     *
     * A state's arcs are stored in ascending letter order, so the scan stops as
     * soon as it passes the wanted letter.
     */
    getArc(ref: number, letter: number): number;
    /** Maps a code point to its letter index, or -1 when the character is not in the alphabet. */
    getLetter(charCode: number): number;
    has(word: string): boolean;
    hasPrefix(prefix: string): boolean;
}