The implicit index access example seemed not working

[WeihanLi]

Type of issue

Code doesn't work

Description

The implicit index access example seemed not working

int[] numbers =
{
   [^1] = 4,
   [^2] = 3,
   [^3] = 2,
   [^4] = 1,
};

CS0131: The left-hand side of an assignment must be a variable, property or indexer

And I'm using the latest vs preview and targeted net9.0 with .NET 9 RC1 SDK installed

Page URL

https://learn.microsoft.com/en-us/dotnet/csharp/whats-new/csharp-13#implicit-index-access

Content source URL

https://github.com/dotnet/docs/blob/main/docs/csharp/whats-new/csharp-13.md

Document Version Independent Id

587ed47f-f532-e018-9b0d-6ee76afd20e4

Article author

@BillWagner

Metadata

• ID: c36588d0-6bdf-1740-220c-10b20bb88730
• Service: dotnet-csharp
• Sub-service: whats-new

[WeihanLi]

The array needs to be inside of an object, there's an example

internal class ImplicitIndexAccessSample
{
    public static void Main()
    {
        var a = new TestClass()
        {
            Numbers =
            {
                [0] = 3,
                [^1] = 1
            }
        };
        foreach (var item in a.Numbers)
        {
            Console.WriteLine(item);
        }

        // output 3 0 1
    }
}

file sealed class TestClass
{
    public int[] Numbers { get; init; } = new int[3];
}