import { Logger } from './logger';
import { ParseOptions } from '../settings/options';
import * as i0 from "@angular/core";
/**
 * The object returned by the detailedStringify function in DeepComparer.
 * Contains the stringified value as well as the number of times the maximum stringify depth was reached.
 */
export interface DetailedStringifyResult {
    result: string | null;
    depthReachedCount: number;
}
/**
 * A service for comparing two variables by value instead of by reference
 */
export declare class DeepComparer {
    private logger;
    constructor(logger: Logger);
    /**
     * Tests if two objects are equal by value
     *
     * @param a - The first object
     * @param b - The second object
     * @param compareDepth - How many levels deep to compare
     * @param options - The current parseOptions
     */
    isEqual(a: any, b: any, compareDepth?: number, options?: ParseOptions): boolean;
    /**
     * Like JSON.stringify, but stringifies additional datatypes that would have been
     * nulled otherwise. It also doesn't throw errors on cyclic property paths.
     *
     * If obj can't be stringified for whatever reason, returns null.
     *
     * @param obj - The object to stringify
     * @param depth - How many levels deep to stringify
     */
    detailedStringify(obj: any, depth?: number): DetailedStringifyResult;
    /**
     * Travels on object and replaces cyclical references with null
     *
     * @param obj - The object to travel
     * @param stack - To keep track of already travelled objects
     * @param depth - How many levels deep to decycle
     * @param depthReached - An object to track the number of times the max depth was reached
     */
    decycle(obj: any, stack: any[] | undefined, depth: number | undefined, depthReached: {
        count: number;
    }): any;
    /**
     * Returns true when all the properties of one object equal those of another object, otherwise false.
     *
     * @param a - The first object
     * @param b - The second object
     */
    objEqualsProperties(a: any, b: any): boolean;
    static ɵfac: i0.ɵɵFactoryDeclaration<DeepComparer, never>;
    static ɵprov: i0.ɵɵInjectableDeclaration<DeepComparer>;
}