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lang: ja-jp
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# C# 空の`IAsyncEnumerable<T>` を生成する 2022-08-30

> Create empty IAsyncEnumerable
> https://stackoverflow.com/questions/59443429/create-empty-iasyncenumerable

> reactive/Ix.NET/Source/System.Linq.Async/System/Linq/Operators/Empty.cs
> https://github.com/dotnet/reactive/blob/c25e4841516f76aef997c1bb5c5eeb7f9a07a7ca/Ix.NET/Source/System.Linq.Async/System/Linq/Operators/Empty.cs

> System.Linq.Async
> https://www.nuget.org/packages/System.Linq.Async/

using System.Linq;

private async Task<IAsyncEnumerable<T>> GetPostalCodesAsync<T>()
{
    if (WpfUtil.IsInDesignMode)
    {
        return AsyncEnumerable.Empty<T>();
    }
    ・・・   
}

###### tags: `C#` `IAsyncEnumerable` `System.Linq.Async`