/**
 * Cologne Phonetic Algorithm
 * src/phonetic/Cologne.ts
 *
 * @see https://en.wikipedia.org/wiki/Cologne_phonetics
 *
 * Cologne phonetics, also known as `Kölner Phonetik` or the `Cologne process`,
 * is a phonetic algorithm that assigns a sequence of digits, referred to as the
 * phonetic code, to words. The purpose of this method is to ensure that words
 * with identical sounds receive the same code. This algorithm can facilitate a
 * similarity search among words.
 *
 * Cologne phonetics is associated with the well-known Soundex phonetic algorithm,
 * yet it is specifically optimized for the German language. This algorithm was
 * introduced by Hans Joachim Postel in 1969.
 *
 * The Cologne phonetic algorithm works by mapping letters to digits, ignoring
 * certain letters, and applying specific rules to handle character combinations.
 *
 * @module Phonetic/Cologne
 * @author Paul Köhler (komed3)
 * @license MIT
 */
import type { PhoneticOptions } from '../utils/Types';
import { Phonetic } from './Phonetic';
/**
 * Cologne class extends the Phonetic class to implement the Cologne phonetic algorithm.
 */
export declare class Cologne extends Phonetic {
    protected static default: PhoneticOptions;
    /**
     * Constructor for the Cologne class.
     *
     * Initializes the Cologne phonetic algorithm with the mapping and options.
     *
     * @param {PhoneticOptions} [opt] - Options for the Cologne phonetic algorithm
     */
    constructor(opt?: PhoneticOptions);
    /**
     * Adjusts the phonetic code by removing all '0's except the first character.
     *
     * @param {string} code - The phonetic code to adjust
     * @returns {string} - The adjusted phonetic code
     */
    protected adjustCode(code: string): string;
}