// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
 
using Microsoft.CodeAnalysis.Text;
using Roslyn.Utilities;
 
namespace Microsoft.CodeAnalysis
{
    /// <summary>
    /// Extension methods associated with ConsList.
    /// </summary>
    internal static class ConsListExtensions
    {
        public static ConsList<T> Prepend<T>(this ConsList<T>? list, T head)
        {
            return new ConsList<T>(head, list ?? ConsList<T>.Empty);
        }
 
        public static bool ContainsReference<T>(this ConsList<T> list, T element)
        {
            for (; list != ConsList<T>.Empty; list = list.Tail)
            {
                if (ReferenceEquals(list.Head, element))
                {
                    return true;
                }
            }
 
            return false;
        }
    }
}