/**
 * Assign lexrank scores to sentences.
 *
 * @param {Options | undefined} [options] Plugin options.
 * @returns Transform.
 */
export default function retextLexrank(options?: Options | undefined): (tree: Root, file: VFile) => undefined;
/**
 * Extracted group of sentence nodes under the same parent.
 */
export type ExtractedUnit = {
    /**
     * Sentences with stemmed words.
     */
    sentences: string[][];
    /**
     * Sentence nodes.
     */
    sentenceNodes: Nodes[];
    /**
     * Delimiter marker.
     *
     * Extract sentences from the tree.
     */
    delimiter: boolean;
};
export type VFile = import("vfile").VFile;
export type Root = import("nlcst").Root;
export type Nodes = import("nlcst").Nodes;
export type Paragraph = import("nlcst").Paragraph;
export type Sentence = import("nlcst").Sentence;
export type SentenceContent = import("nlcst").SentenceContent;
export type Word = import("nlcst").Word;
export type Delimiter = (text: string, node: Paragraph) => boolean;
/**
 * Plugin options.
 */
export type Options = {
    /**
     * Maximum number of sentences per chunk. Defaults to `Infinity`.
     */
    maxSentencesPerChunk?: number | undefined;
    /**
     * Optional chunk delimiter matcher.
     */
    delimiter?: string | RegExp | Delimiter | undefined;
};