Functional Reactive Programming for .NET.

Two composable primitives: a stream of discrete events, and a cell holding a value over time. A transaction system updates everything you build from them atomically, so no observer ever sees a half-updated graph or a value that never logically existed. In C# and F#.

Get started Core concepts API reference 

StreamSink<int> s = Stream.CreateSink<int>();
Cell<int> c = s.Hold(0);
IListener l = c.Listen(Console.WriteLine);

s.Send(2);   // prints 2
s.Send(9);   // prints 9

l.Unlisten();

SodaFlow is based on Sodium, the Functional Reactive Programming library by Stephen Blackheath and Anthony Jones, and began as that project's .NET implementation. The model documented here is Sodium's: streams, cells, behaviors, transactions, and the denotational semantics that SodaFlow implements unchanged. The credit for that model belongs upstream. Sodium's implementations for Java, Scala, C++, Kotlin, TypeScript, and Rust live under the SodiumFRP organization.

Start here

Getting started Install a package and run your first program. Which package do I install? This page picks one of the published packages for you. Core concepts Streams, cells, behaviors, and transactions. Operation reference Every operation, C# and F# side by side. Cookbook Recipes for the things that come up constantly. Sample applications Full WPF and Avalonia apps over shared view models. API reference Generated from the source.

Going deeper

Transactions Atomicity, simultaneity, and why glitches cannot happen. Feedback loops Values that depend on their own past. Switch and dynamic graphs Changing the graph's shape at runtime. Listener lifetimes The most common way to break a SodaFlow program. Time and timers Clocks, alarms, and deterministic tests. Asynchronous work Running tasks without breaking the model. Reactive collections Large keyed collections where an edit reaches only the rows bound to it. Data binding Exposing a graph to XAML as properties and commands. Maybe, Either and Unit The small functional vocabulary C# does not ship with. Denotational semantics Sodium's formal specification, which SodaFlow is tested against.

Elsewhere

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