/**
 * Gets the boundary name
 * @param contentType - string
 */
export declare function getBoundary(contentType: string): string | undefined;
export declare function getCharsetName(charset: string): string;
/**
 * Decodes mime encoded string to an unicode string
 *
 * @param {String} str Mime encoded string
 * @param {String} [fromCharset='UTF-8'] Source encoding
 * @return {String} Decoded unicode string
 */
export declare function mimeDecode(str?: string, fromCharset?: string): string;