import { Guard } from '../core/guard';
import { GuardResult } from '../core/guard-result';
declare type BooleanRule = {
    type: 'isFalse';
    value: false;
} | {
    type: 'isTrue';
    value: true;
};
export declare class BooleanGuard extends Guard<BooleanRule> {
    constructor();
    /**
     * Checks if value is a false boolean.
     * @remarks Chainable method.
     */
    isFalse(): this;
    /**
     * Checks if value is a true boolean.
     * @remarks Chainable method.
     */
    isTrue(): this;
    /**
     * @override
     * @param rule
     * @param value
     */
    protected checkRule(rule: BooleanRule, value: boolean): GuardResult;
    /**
     * @override
     */
    protected typeGuard(): void;
}
export {};