export declare const INVALID_POINT: number;
export type IPoint = {
    [0]: number;
};
export type IReadonlyPoint = Readonly<IPoint>;
export declare function make_point_invalid(point: IPoint): void;
export declare function is_valid_point(point: IReadonlyPoint): boolean;
export declare function is_invalid_point(point: IReadonlyPoint): boolean;