/**
 * :::caution Required trait
 *
 * Every entity has to have it.
 * Game state keeps track of every entity in game by their ID's
 *
 * :::
 *
 * > TODO: I might just bake that trait into base Entity class...
 * @category Trait
 */
export declare class IdentityTrait {
    readonly id: number;
}
/**
 * @category Trait
 */
export declare function hasIdentity(entity: any): entity is IdentityTrait;