Flapjax

Flapjax is a programming language built atop JavaScript. It provides a spreadsheet-like dataflow computation style (functional reactive programming), making it easy to create reactive Web pages without the burden of callbacks and potentially inconsistent mutation. Flapjax can be thought of in two ways: either as a library, for use in regular JavaScript programs, or as a new language that the compiler converts into generic JavaScript. In either case, the resulting programs can be run in a regular Web browser. In addition, Flapjax comes with persistent storage and a simple API that masks the complexity of using AJAX, along with sharing and access-control for server data.

The Flapjax compiler is written in Haskell.

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