/** Classic trie data structure. */
export declare class Trie<T> {
    /** Entrypoint for the trie. */
    private head;
    /**
     * Adds a word to the trie, which will point to a value.
     *
     * @param word - The word to add.
     * @param addValue - A callback function for how to add the word to the
     *   trie. It is provided the current value of the word added, if any.
     *   This allows for merging overlapping values.
     */
    add(word: string, addValue?: (cur?: T) => T): void;
    /** Determines if a word is in the trie. */
    has(word: string): boolean;
    /** Returns the segments found when traversing the trie for the given word. */
    segments(word: string): T[] | null;
    /** Returns the longest/last segment for a word. */
    lastSegment(word: string): T | null;
    /** Removes a word from the trie. */
    remove(word: string): void;
    private traverse;
    private tryDelete;
}