import type { Alphabet } from "./common";
/**
 * `UnicodeSubsetAlphabet` parameters
 */
export interface UnicodeSubsetAlphabetParams {
    start?: number | string;
    end?: number | string;
}
/**
 * And alphabet which is build from a straight (without skips) subset from the Unicode
 * characters set
 */
export declare class UnicodeSubsetAlphabet implements Alphabet {
    #private;
    /**
     * The entire Unicode characters set alphabet
     */
    static readonly unicode: UnicodeSubsetAlphabet;
    /**
     * The ASCII characters set alphabet
     */
    static readonly ascii: UnicodeSubsetAlphabet;
    readonly length: number;
    constructor({ start, end, }?: UnicodeSubsetAlphabetParams);
    getAt(index: number): string;
    indexOf(char: string): number;
    [Symbol.iterator](): Iterator<string>;
    has(char: string): boolean;
}