export declare function dbcswidth(str: string): number;
/**
* calculate width of string.
* @params {string} widthType - calculate width by wcwidth or String.length
* @params {string} str - string to calculate
*/
export declare function getWidth(widthType: string, str: string): number;
/**
* calculate the position that the prefix of string is a specific width
* @params {string} widthType - calculate width by wcwidth or String.length
* @params {string} str - string to calculate
* @params {number} width - the width of target string
*/
export declare function indexOfWidth(widthType: string, str: string, width?: number): number;
/**
* extract parts of string, beginning at the character at the specified position,
* and returns the specified width of characters. if the character is incomplete,
* it will be replaced by space.
* @params {string} widthType - calculate width by wcwidth or String.length
* @params {string} str - string to calculate
* @params {number} startWidth - the beginning position of string
* @params {number} width - the width of target string
*/
export declare function substrWidth(widthType: string, str: string, startWidth: number, width?: number): string;