// ***********************************************************************
// Copyright (c) 2009 Charlie Poole, Rob Prouse
//
// Permission is hereby granted, free of charge, to any person obtaining
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// "Software"), to deal in the Software without restriction, including
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// permit persons to whom the Software is furnished to do so, subject to
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//
// The above copyright notice and this permission notice shall be
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// ***********************************************************************

using System;

namespace NUnit.Framework.Constraints.Comparers
{
    /// <summary>
    /// Interface for comparing two <see cref="Object"/>s.
    /// </summary>
    internal interface IChainComparer
    {
        /// <summary>
        /// Method for comparing two objects with a tolerance.
        /// </summary>
        /// <param name="x">The first object to compare.</param>
        /// <param name="y">The second object to compare.</param>
        /// <param name="tolerance">The tolerance to use when comparing the objects.</param>
        /// <param name="topLevelComparison">Flag indicating whether or not this is the top level comparison.</param>
        /// <returns>
        ///     <c>null</c> if the objects cannot be compared using the method.
        ///     Otherwise the result of the comparison is returned.
        /// </returns>
        bool? Equal(object x, object y, ref Tolerance tolerance, bool topLevelComparison = true);
    }
}
