/**
 * @description trim spaces from start and end, replace multiple spaces with one.
 * @example
 * @ApiProperty()
 * @IsString()
 * @Trim()
 * name: string;
 * @returns PropertyDecorator
 * @constructor
 */
export declare function Trim(): PropertyDecorator;
export declare function ToBoolean(): PropertyDecorator;
/**
 * @description convert string or number to integer
 * @example
 * @IsNumber()
 * @ToInt()
 * name: number;
 * @returns PropertyDecorator
 * @constructor
 */
export declare function ToInt(): PropertyDecorator;
/**
 * @description transforms to array, specially for query params
 * @example
 * @IsNumber()
 * @ToArray()
 * name: number;
 * @constructor
 */
export declare function ToArray(): PropertyDecorator;
export declare function ToLowerCase(): PropertyDecorator;
export declare function ToUpperCase(): PropertyDecorator;