/**
 * Checks whether or not a value is a boolean.
 *
 * @param value
 */
export declare function isBoolean(value: any): value is boolean;
/**
 * Checks whether or not a value is a function.
 *
 * @param value
 */
export declare function isFunction(value: any): value is Function;
/**
 * Checks whether or not a value is a number.
 *
 * @param value
 */
export declare function isNumber(value: any): value is number;
/**
 * Checks whether or not a value is a string.
 *
 * @param value
 */
export declare function isString(value: any): value is string;