export declare const $track: unique symbol;
export declare const $encoder: unique symbol;
export declare const $decoder: unique symbol;
export declare const $getByIndex: unique symbol;
export declare const $deleteByIndex: unique symbol;
/**
 * Used to hold ChangeTree instances whitin the structures
 */
export declare const $changes: unique symbol;
/**
 * Used to keep track of the type of the child elements of a collection
 * (MapSchema, ArraySchema, etc.)
 */
export declare const $childType: unique symbol;