$ show reactivemarbles/DynamicData
DynamicData is a mature, production-grade .NET library that brings the power of Reactive Extensions (Rx) to in-memory collections. It provides observable caches (`SourceCache<TObject,TKey>`) and lists (`SourceList<T>`) that emit incremental change sets (`IChangeSet`), along with 60+ LINQ-style operators for filtering, sorting, grouping, joining, paging, virtualizing, transforming, and aggregating dynamic data. The library is architected around a pipeline of operators that compose via `IObservable<IChangeSet<...>>`, enabling reactive, real-time data processing and UI binding. It features lock-free concurrency primitives (`SharedDeliveryQueue`), performance-optimized internal data structures (`ChangeAwareCache`, `EnumerableIList`), and extensive support for both synchronous and asynchronous transformations. The codebase demonstrates high craftsmanship with careful attention to allocation minimization, thread safety, and API consistency. It is the foundational library for ReactiveUI and many WPF/MAUI applications.
The LLM identified 3 files worth highlighting for reuse:
A zero-allocation, value-type `Optional<T>` that provides a safe alternative to null for representing optional presence. It includes implicit conversions, equality, and observable extensions (`OptionObservableExtensions`). This pattern is generic, framework-agnostic, and can be extracted into any .NET project needing a lightweight option type.
A struct-based `IEnumerable<T>` implementation that wraps an `IList<T>` without allocating an enumerator object on the heap. It is used internally to avoid allocations when iterating change sets. The pattern demonstrates deep understanding of .NET memory model and can be reused wherever low-allocation enumeration over indexed collections is required.
An enhanced `ObservableCollection<T>` that supports suspending and resuming collection change notifications, allowing batch modifications without intermediate UI updates. It maintains a reference count for nested suspensions and automatically re-raises a single `Reset` notification on resume. This is a self-contained pattern useful for any UI binding scenario that requires bulk updates.