export declare class AttributeBag<T> {
    #private;
    /**
     * Creates an instance of AttributeBag.
     * @param {T} [attributes]
     * @memberof AttributeBag
     */
    constructor(attributes?: Partial<T>);
    /**
     * Get all of the items in the attribute object.
     *
     * @return {Partial<T>}
     * @memberof AttributeBag
     */
    all(): Partial<T>;
    /**
     * Get a given attribute from the attribute object.
     *
     * @template U
     * @param {(keyof T | string)} key
     * @param {U} [defaultValue]
     * @return {T}
     * @memberof AttributeBag
     */
    get<U = any>(key: keyof T | string, defaultValue?: U): U;
    /**
     * Set a given attribute in the attribute object.
     *
     * @template T
     * @param {(keyof T | string)} key
     * @param {U} value
     * @memberof AttributeBag
     */
    set<U>(key: keyof T | string, value: U): void;
    /**
     * Set many given attributes in the attribute object.
     *
     * @param {object} value
     * @memberof AttributeBag
     */
    setMany(value: object): void;
    /**
     * Determine if a given attribute exists in the attribute object.
     *
     * @param {keyof T} key
     * @return {boolean}
     * @memberof AttributeBag
     */
    has(key: keyof T): boolean;
    /**
     * Determine if a given attribute exists in the attribute object
     * and is not `undefined` or `null` which equal missing contents.
     *
     * @param {keyof T} key
     * @return {boolean}
     * @memberof AttributeBag
     */
    hasStrict(key: keyof T | string): boolean;
    /**
     * Determine if a given attribute is missing in the attribute object.
     *
     * @param {keyof T} key
     * @return {boolean}
     * @memberof AttributeBag
     */
    missing(key: keyof T): boolean;
    /**
     * Remove an item from the attributes.
     *
     * @param {keyof T} key
     * @memberof AttributeBag
     */
    forget(key: keyof T): void;
    /**
     * Remove all items from the attributes.
     *
     * @memberof AttributeBag
     */
    flush(): void;
    /**
     * Only include the given attribute from the attribute object.
     *
     * @param {(keyof T)[]} keys
     * @return {Record<string, any>}
     * @memberof AttributeBag
     */
    only(keys: (keyof T)[]): Record<string, any>;
    /**
     * Exclude the given attribute from the attribute object.
     *
     * @param {(keyof T)[]} keys
     * @return {Record<string, any>}
     * @memberof AttributeBag
     */
    except(keys: (keyof T)[]): Record<string, any>;
}