Fork 0

39 lines
1.7 KiB

// 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 System;
using System.Collections.Generic;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
namespace CommunityToolkit.HighPerformance;
/// <summary>
/// Helpers for working with the <see cref="List{T}"/> type.
/// </summary>
public static class ListExtensions
/// <summary>
/// Creates a new <see cref="Span{T}"/> over an input <see cref="List{T}"/> instance.
/// </summary>
/// <typeparam name="T">The type of elements in the input <see cref="List{T}"/> instance.</typeparam>
/// <param name="list">The input <see cref="List{T}"/> instance.</param>
/// <returns>A <see cref="Span{T}"/> instance with the values of <paramref name="list"/>.</returns>
/// <remarks>
/// Note that the returned <see cref="Span{T}"/> is only guaranteed to be valid as long as the items within
/// <paramref name="list"/> are not modified. Doing so might cause the <see cref="List{T}"/> to swap its
/// internal buffer, causing the returned <see cref="Span{T}"/> to become out of date. That means that in this
/// scenario, the <see cref="Span{T}"/> would end up wrapping an array no longer in use. Always make sure to use
/// the returned <see cref="Span{T}"/> while the target <see cref="List{T}"/> is not modified.
/// </remarks>
public static Span<T> AsSpan<T>(this List<T>? list)
return CollectionsMarshal.AsSpan(list);