/**
 * Convert full-width characters to half-width characters
 */
export declare function fullWidthToHalfWidth(str: string): string;
/**
 * Check if the string contains spam information
 */
export declare function containsSpam(str: string): boolean;
/**
 * Clean airport name
 */
export declare function cleanAirportName(name: string): string;
/**
 * Validate airport data
 */
export declare function isValidAirport(name: string, iataCode: string): boolean;