Wolfgang.Extensions.IAsyncEnumerable

A collection of extension methods for IAsyncEnumerable<T> in .NET — chunking, side-effect projection, eager iteration, and emptiness / quantifier predicates. Built async-first with strict analyzer enforcement and multi-TFM packaging.

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📦 Installation

dotnet add package Wolfgang.Extensions.IAsyncEnumerable

NuGet Package: Wolfgang.Extensions.IAsyncEnumerable

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📄 License

This project is licensed under the MIT License. See the LICENSE file for details.

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📚 Documentation

• GitHub Repository: https://github.com/Chris-Wolfgang/IAsyncEnumerable-Extensions
• API Documentation: https://Chris-Wolfgang.github.io/IAsyncEnumerable-Extensions/
• CHANGELOG: CHANGELOG.md
• Contributing Guide: CONTRIBUTING.md
• Formatting Guide: docs/README-FORMATTING.md
• DocFX Version Picker Troubleshooting: docs/DOCFX-VERSION-PICKER.md
• Release Workflow Setup: docs/RELEASE-WORKFLOW-SETUP.md
• Workflow Security: docs/WORKFLOW_SECURITY.md

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✨ Extension methods

All nine extensions live on IAsyncEnumerableExtensions (namespace Wolfgang.Extensions.IAsyncEnumerable). See the API documentation for signatures, parameter details, and per-method examples.

Method	Purpose
ChunkAsync<T>(source, maxChunkSize, ct)	Splits the stream into fixed-size ICollection<T> batches.
DoAsync<T>(source, Action<T>, ct)	Side-effect projection — runs a sync action per element; yields the originals unchanged.
DoAsync<T>(source, Func<T, Task>, ct)	Side-effect projection — runs an async action per element; yields the originals unchanged.
ForEachAsync<T>(source, Action<T>, ct)	Eager iteration with a sync action — terminal.
ForEachAsync<T>(source, Func<T, Task>, ct)	Eager iteration with an async action — terminal.
IsEmptyAsync<T>(source, ct)	true if the stream yields zero elements. Short-circuits on the first element.
IsNullOrEmptyAsync<T>(source?, ct)	true if the stream is null or yields zero elements. Null-tolerant.
NoneAsync<T>(source, ct)	true if the stream yields zero elements (same shape as IsEmptyAsync, different naming).
NoneAsync<T>(source, predicate, ct)	true if no element satisfies the predicate. Short-circuits on the first match.

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🚀 Quick Start

using Wolfgang.Extensions.IAsyncEnumerable;

// Chunk an async stream into batches of up to 100, with logging side-effect
await foreach (var batch in source
    .DoAsync(x => logger.LogInformation("Processing {Item}", x))
    .ChunkAsync(maxChunkSize: 100, token: cancellationToken))
{
    await ProcessBatchAsync(batch);
}

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🎯 Target Frameworks

net462, netstandard2.0, net8.0, net10.0 — single NuGet package, picks the best fit at consume time.

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🔍 Code Quality

This project enforces strict analyzer rules and async-first patterns via:

• Microsoft.CodeAnalysis.NetAnalyzers (built into the SDK) — correctness + performance
• Roslynator.Analyzers — refactoring + style
• AsyncFixer — async/await anti-patterns
• Microsoft.VisualStudio.Threading.Analyzers — thread-safety + async patterns
• Microsoft.CodeAnalysis.BannedApiAnalyzers — banned synchronous APIs (see BannedSymbols.txt)
• Meziantou.Analyzer — broad code-quality rules
• SonarAnalyzer.CSharp — industry-standard analysis
• Microsoft.CodeAnalysis.PublicApiAnalyzers — public-API surface change detection (see src/.../PublicAPI.Shipped.txt)

<TreatWarningsAsErrors>true</TreatWarningsAsErrors> is active for Release builds, so any analyzer warning blocks the release pipeline.

BannedSymbols.txt prohibits the usual sync-over-async traps: Task.Wait() / Task.Result, Thread.Sleep, sync file/stream I/O, Parallel.For/ForEach, WebClient, BinaryFormatter.

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🛠️ Building from Source

git clone https://github.com/Chris-Wolfgang/IAsyncEnumerable-Extensions.git
cd IAsyncEnumerable-Extensions
dotnet restore
dotnet build --configuration Release
dotnet test  --configuration Release

SDK requirement: the version installed by .github/workflows/pr.yaml (currently .NET 10 + side-by-side SDKs for the older TFMs). See docs/README-FORMATTING.md for the source-formatting workflow.

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🙏 Acknowledgments

• Microsoft.Bcl.AsyncInterfaces — IAsyncEnumerable<T> backport for net462 / netstandard2.0
• The analyzer-package authors above
• The .NET team for IAsyncEnumerable<T> and the async-stream language support that made this library a one-file project