import GridData from '../grid.js';
import { State } from '../primitives.js';
import Symbol from './symbol.js';
/**
 * All symbols which contain a number should extend this class to be compatible with off by X rules.
 */
export default abstract class NumberSymbol extends Symbol {
    readonly x: number;
    readonly y: number;
    readonly number: number;
    constructor(x: number, y: number, number: number);
    abstract countTiles(grid: GridData): {
        completed: number;
        possible: number;
    } | null;
    validateSymbol(grid: GridData): State;
    withNumber(number: number): this;
}
export declare const instance: undefined;