// Copyright (c) Microsoft Corporation. All rights reserved.

// Licensed under the MIT license.

namespace Microsoft.ClearScript

{

/// <summary>

/// Represents an undefined value.

/// </summary>

/// <remarks>

/// Some script languages support one or more special non-<c>null</c> values that represent

/// nonexistent, missing, unknown, or undefined data. The ClearScript library maps such values

/// to instances of this class.

/// </remarks>

public class Undefined

{

/// <summary>

/// The sole instance of the <see cref="Undefined"/> class.

/// </summary>

public static readonly Undefined Value = new Undefined();

private Undefined()

{

}

#region Object overrides

/// <summary>

/// Returns a string that represents the current object.

/// </summary>

/// <returns>A string that represents the current object.</returns>

/// <remarks>

/// The <see cref="Undefined"/> version of this method returns "[undefined]".

/// </remarks>

public override string ToString()

{

return "[undefined]";

}

#endregion

}

}